KS3 20Activities

KS3

7I Energy resources

QCA sobj Suggested action SPT relevent slide:

Identify fuels as sources of heat, light (a) Review student understanding of the word 'fuel', and brainstorm types of fuel and what they

and movement are used for. Introduce the definition that when fuels react with oxygen they produce energy

(b) Use a bunsen burner to heat water until it boils. Describe the water and ask where the

energy has come from



Recall that light, heat and movement (a) Demonstrate igniting a bubble of methane. Highlight that the methane has reacted with

are all forms of energy oxygen and heat, sound and light energy is given off. Discuss whether the explosion could also

move objects

(b) Students to work in small groups and to think of as many everyday uses of the word

'energy'. Typical answers include the word in many everday contexts eg ' I havent got the

energy for this'. Use the answers to discuss and develop the idea that there are different types

of energy such as heat, light, movement and sound

Recognise simple energy transfers (a) Discuss ways in which energy can be stored eg in food, in petrol, by lifting objects up or

stored in a spring, and then ways in which energy can be detected ie as heat, light, movement,

sound and electricity

(b) Consider the energy transfers in a light bulb. What type of energy has gone in (electricity)

and what types come out (heat and sound)

(c) Use a circus of toys and consider energy transfers in each. Students could identify the type

of energy store and what this energy has been converted into.

Identify some fossil fuels (a) Show students pieces of coal and sealed samples of oil. Identify them as being 'fossil fuels'

and ask what students understand by the word 'fossil'

(b) Students to present a poster on what fossil fuels are, based on information from a video,

software or internet resource;

Give examples of how we can save (a) Discuss the fuels of the future, in particular, emphasise the need to use less fossil fuel. What

fuels could be done in everyday life and how much would people be prepared to sacrifice eg. smaller

car or less flights abroad. Consider whether sacrifices need to be made - think about simple

changes of behaviour, such as turning off computers and electrical items on standby, or boiling

only the amount of water that is needed rather than a full kettle, running a shower for 1 minute

less, walking/cycling rather than driving, etc.

(b) Show the students images of various energy sources eg wind turbine, waterfall, bunsen

burner and ask to categorise as fossil fuel or not.

Know that fossil fuels are non- (a) Demonstrate burning a wooden splint or match. Emphasise that when the fuel is gone we

renewable cant use it again. Consolidate by showing a cigarette lighter and asking what use is it when it is

empty? Define 'non-renewable fuels' as those that cant be renewed easily and so will eventually

be used up

(b) Brainstorm what fuels get used up when they burn (all of them!) but then ask which can be

replaced within a short time. Identify wood, wax, and alcohol as fuels that can be produced

relatively quickly. Highlight that there are other sources of energy than fuel.

Understand why we must conserve (a) Students could make a leaflet suitable for Year 6 pupils raising the issues of using fossil

fossil fuels fuels and suggested ways to conserve them

(b) Distinguish between 'conserve' used here as something people can do to minimise

consumption and 'the principle of conversation of energy' which students will meet later which

has a stricter use

Know how fossil fuels were formed (a) Students to make cards with labels for significant eras during Earth's history eg: Formation

of Earth, Formation of Oceans; First Life, Jurassic and First Man. Position these to the correct

scale around the perimeter of the classroom and emphasise that there has been a very long

time for fossil fuels to be made, that the fuels take millions of years to form but that we are

using them up at an much faster rate

(b) Show a suitable video or animation that shows the formation of fossil fuels, in particular, the

time scale and the fact that they were originally made up of living matter

Know that fossil fuels do not last (a) Students to design a pamphlet for younger students summarising the problems about using

forever fossil fuels (they are non-renewable, contribute to global warming and acid rain, and countries

are not self sufficient)

(b) Analyse data that shows type of fuel, energy it produces per unit volume, cost, and time to

replenish

Understand the difference between (a) Demonstrate the use of a photovoltaic device, and allow students to highlight the advantage

renewables and non-renewables that no fuel is being used. Identify solar energy as being a renewable source of energy.

Brainstorm all energy resources and students to separate into those that are 'renewable' and

those that are 'non-renewable'

(b) Make a solar panel by heating water left in the sun. Students compete in trying to make their

water the hottest by using aluminium cartons and black paper. Ask the question 'Is heating

water like this better than using electricity?' and discuss answers. Students may consider

electricty as being 'better' because it is percieved as being more efficient but the definition of

what is a better fuel could develop wider issues eg debate about environmental concerns. Also

note that electricity can be produce by different resources.



Identify renewable energy resources (a) Students could play snap by using cards with different energy sources draw or written on

from a list them. When two renewable energy sources are consecutive we have 'snap'

(b) Students create their own wordsearch using a list of renewable energy source and swap

with a partner

Explain how energy resources are (a) Students to consider a scenerio (such as SATIS: Ashton Island) where they have to survive

renewable on a desert island without fossil fuels. They are to consider strategies for maintaining short and

long-term survival (eg how to cook food, forestry of trees) explaining why their suggestions

involve renewable energy resources

(b) Ask students to invent a useful device for the future. Encourage creative approaches, but

based on science, eg wind farms at sea. This workcould be used to generate discussion on

pros and cons of renewable energy sources and a comparison of energy resources available to

less-developed nations.

Know that renewable energy (a) Show students a wind up radio or torch. Ask students how it works and why they are so

resources are used to generate important in less-developed or isolated countries. Try to elicit the response that a small

electricity generator converts movement to electricity which charges a battery. Consider ways to turn the

handle using renewable energy resources eg falling water, wind, wave (b) Provide students

information about contemporary hybrid cars that switch from fuel driven to battery powered.

Survey friends and relatives to find to if people would ever consider buying one. (c) Research

the National Grid and finding out how much 'conventional' electricity comes from renewable

energy sources









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KS3

Explain how non-renewable energy (a) Show students a model generator or wind up radio. Highlight an energy transfer in the

resources are used to generate generator where movement energy is converted into electricity. Challenge students to devise

electricity ways in which coal, oil or gas could be used to turn the handle on the generator. Try to elicit

need for steam turning turbines as efficiently as possible

(b) Students to make a model power station using moveable parts eg turbine circle and paper

fastener, identifying key energy changes

Know that food is the energy resource (a) Use custard powder and a candle to blow the lid from a large coffee tin (full risk asessments

for animals needed). Highlight that the stored energy in the powder and the oxygen has been converted to

heat, light and sound

(b) Ask students in groups to investigate the energy resource in foods, eg breakfast cereal,

crisps, marshmallow by burning them and measuring the rise in temperature of some water.

Establish that although our bodies don't 'burn' fuels by lighting them like this, we do burn them

in a different way

Know that light is the energy source (a) Compare plants to a laptop. The laptop can run from battery power only but the battery is

for plants topped up by plugging it into the mains every now and again. Similarly, plants use energy all

the time (respiration) but a good dose of sunshine tops up the sugar levels which is used as an

energy resource (photosynthesis).

(b) Students to handle molecular models of large sugar molecules, which they can break up.

Emphasise that the plant gets it energy by breaking up the molecules but most plants also use

sunlight energy to make the sugar molecule up again.

Identify energy flow through food (a) Students to devise their own food chains that include humans. Question what happens to the

chain energy contained in our food. Try to elicit the answers: it is used to make us grow (ie some is

stored), it is used by us to do things, and some of it is passed straight out of the body. Guess

the fraction of energy that is stored at each stage of the food chain considering how much food

an animal eats in its lifetime compared to its body mass

(b) Look at packets of various foods and find the energy label in kJ or cal. Introduce a calorie as

an old fashioned measured of energy and discuss the consequences of eating more or less

than the energy you burn

Know that a food chain can be (a) Students to devise their own food chains and then asked "where does this get its energy

extended to show the link to sunlight from", pointing at the first card. Keep asking the same question until they conclude that plants

get their energy from the Sun. Students to write this conclusion in their notes

(b) Students to examine in small groups why wide animals often give birth during the Spring eg

many birds. Relate to availability of food and increase in sunlight.



Understand that the sun is the energy (a) Students to make 16 cards by drawing symbols of their choice on the card. The cards

source for almost all the Earth’s produced will have symbols of : Sun (x4), trees, coal, fire, wind, turbine, electricity, grass, cows,

energy resources milk, plankton, oil, nuclear. Ask students to arrange cards into 4 energy chains (Sun to trees to

coal to fire; Sun to wind to turbine to electricty, Sun to grass to cows to milk; and Sun to

plankton to oil Conclude that all energy except nuclear come from the Sun

(b) Imagine a scenario when a large volcano has erupted and the entire Earth is covered in a

permanent thick dust cloud that sunlight cannot penetrate. How would people survive with no

sun when the fossil fuels run out? Encourage imaginative answers that use science eg large

solar panels in space but also encourage answers that rely on nuclear and tidal power





Know that different fuels produce (a) Burn various types of fuel in spirit burners beneath a beaker of water and compare

different amounts of energy (including temperature rise.

foods) (b) Compare the energy labels on different food products and tabulate which foodstuffs give the

most energy per 100g. Keep a diary of foods eaten in a day and total the amount of energy

consumed in a day. Students could be provided with a list of activities and their corresponding

energy expenditure. They could then work out if they are consuming more or less energy than

they use.

(c) Research the energy capacity of different fuels, presenting in a display

Know how to use fuels economically (a) Discuss the statement 'Buses are more fuel economical than cars'. Highlight that buses use

more energy than most cars so how can this statement be correct?

(b) Research then produce a display comparing how much energy per passenger for cars,

buses, trains, planes. Widen the perspective to include other environmental factors such as

global warming and ease of use so that students can appreciate a balanced argument

(c) Relate to reasons as to why it is considered important not to 'waste energy'

Compare advantages and limitations (a) Brainstorm the advantages of fossil fuels and the disadvantages of fossil fuels. Repeat for

of energy resources the advantages and disadvantages of renewable energy. Discuss differences and what would

make an ideal fuel.

(b) Match pairs of cards that show name of energy resource and advantages/limitations. A

game could be made of this by turning the cards face down and the students have to remember

the location.



7J Electrical circuits

sobj Suggested action SPT relevent slide:

Recognise that a circuit must be (a) Review students' knowledge and understanding of electrical circuits by asking them to

complete to work complete circuits by drawing on correct connections. Discuss results as a class or in small

groups.

(b) Students should construct simple circuits using cells, wires (with insulation) and bulbs or

buzzers.

(c) Ask students or groups to explain their observations to others.

Know how a switch can be used to (a) Students construct (i) burglar alarm, (ii) pressure pad and (iii) steady hand tester.

break a circuit (b) Demonstrate a BIG circuit that circles the room. Students predict whether a bulb will take

longer to light if it is further from the battery. Confront the misconception that energy has to

travel from the battery to the bulb before it works. Use analogy of a fan-belt or rope loop and

demonstrate that if it snaps it can no longer work.

(c) Ask students to fix circuits that are not working.

Can construct simple series circuit (a) Demonstrate how to connect up a circuit using a 12V/24W bulb (car headlamps) with a 12V

with given components (using DC power supply and a large demonstration ammeter emphasing correct procedures.

drawings of components not circuit (b) Examine pre-drawn component diagrams and check if students can assemble correctly.

symbols) (c) Discuss how a torch works. Draw a poster with a moveable part that explains how a torch

works.









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KS3

Can match electrical components (a) Students match circuit symbols to components using mix and match cards.

(switch, lamp, wire, cell) to circuit (b) Emphasise the symbol for a battery of cells, noting that the positive terminal of a standard

symbol cell is the long thin line not the short thick line as many students would expect.

(c) Use interactive software that allows circuit symbols to be dragged on the screen and relate

to real components.

Can construct simple series circuit (a) Students construct circuits using circuit symbol diagrams that are printed on cards.

using circuit diagrams (b) Students discuss and explain the results when more cells are added to a simple circuit that

includes an ammeter and a bulb or buzzer, emphasising the difference in circuit diagram.

(c) Students make a torch from a circuit diagram.



Can draw diagrams of simple circuits (a) Demonstrate a simple circuit using 12V/24W bulb, a 12V DC battery (rather than a power

using correct circuit symbols pack), a switch and a large demonstration ammeter. Ask students to draw correctly the circuit

using symbols and compare, emphasising the need for accuracy.

(b) Use software to drag symbols onto a circuit.

(c) Students design a burglar alarm using symbols.

Know that an electrical circuit is made (a) Investigate which common materials make a bulb light when completing a simple circuit.

from electrical conductors (b) Emphasise the key words 'conductor' and 'insulator', noting that these words also relate to

heat. Define a conductor as a material that easily lets energy pass through.

(c) Look closely at the materials that are used to make up an electrical circuit. Discuss which

parts of the circuit need to be conductors and where insulators would be useful.



Can identify common conductors and (a) Demonstrate burning wood from a pencil connected into a series circuit including a large

insulators ammeter (use a fume cupboard or extractor). Note that the graphite is a conductor because

current is passing but the wood catches fire showing energy doesn't pass through it easily.

(b) Students design a method of testing which materials are conductors, presenting results to

class.

(c) Demonstrate copper-plating using electrolysis of copper sulphate solution, showing that

liquids can also be conductors.

(d) Think about materials that conduct heat: are these materials also good conductors of

electricity?



Understand how switches work in (a) Present students with a diagram of a parallel circuit that uses component drawings only.

parallel circuits Discuss possible positions of switches and what the effect would be of closing each switch.

Students could then try out themselves in small groups.

(b) Present students with a circuit diagram of a parallel circuit using symbols that has several

switches included. Discuss the effect of closing each switch.

Understand how parallel circuits work (a) Students construct a traffic light that follows the correct sequence (i.e. red only, red and

using components other than amber, green only, amber only), presenting results to the class.

switches (e.g. hairdryer) (b) Students construct a 2-speed hairdryer circuit that allows another fan to be incoporated if

required.

(c) Diagnostic questions designed to probe students' ability to recognise equivalent ways of

drawing a circuit with two parallel branches.

Understand that the brightness of (a) Make a huge set of fairy lights and ask students to predict the effect of adding and removing

(identical) bulbs wired in parallel more bulbs.

stays the same whatever the number (b) Use software to predict and test the effect of parallel circuits that have differing numbers of

of components bulbs on each branch. Discuss results.

(c) Relate to students' experience of light bulbs blowing at home. Do all the lights go out, do

they get dimmer, or do they stay the same? The lights in their homes will almost certainly be

parallel wired.

Understand that current is the same (a) Demonstrate using a loop of rope to represent the circuit: the current is represented by the

at all points in a series circuit amount of rope that passes through the hands each second.

(b) Students predict then measure currents at different points in a simple circuit. Discuss class

results. Ensure ammeters are not so sensitive that they cause confusion.

(c) Confront student misconceptions, for example, 'Why do kettles only have one lead?'

Understand that current divides in a (a) Model a parallel circuit using two loops of rope, both being pulled through the hand, which

parallel circuit represents a cell. Relate current to the amount of rope that passes a point each second - both

loops together means more current.

(b) Students work in pairs to build a parallel circuit and to measure the current through the leads

and through each bulb.

(c) Demonstrate a large circuit with two bulbs in parallel, connect in series with a third bulb.

Students predict then test the brightness of each bulb.

Recognise amperes as the unit of (a) Use a fan-belt or rope loop analogy and demonstrate an electric circuit by pulling the rope

measurement for electricity flow around: the amount of rope passing a point each second is the current. Identify an Ampere as a

certain length of rope.

(b) Use a bingo style game that associates quantities to their units.

Know how to measure current using (a) Identify an ammeter as being like a guard in a train station counting the number of carriages

an ammeter passing through every second. In a model railway, a piece of track may have to be removed

and the special station piece has to be inserted instead. In the same way, a circuit must be

broken and the ammeter inserted so it is now part of the circuit.

(b) Demonstrate how to connect up a circuit using a 12V/24W bulb (car headlamps) with a 12V

DC power supply and a large demonstration ammeter emphasing correct procedures.



Understand the difference between (a) Students relate different quantities to their units using a mix and match card game.

current and energy transfer in a circuit (b) Use specialist software where students could be involved in setting challenges or labelling

current and charge flow.

(c) Use an analogy of supermarket deliveries to explain energy transfer. Ask students to

discuss similarities and differences between this analogy and their understanding of electrical

circuits.

Can explain the difference between (a) Discuss the current either side of a motor and relate to where energy is being transferred.

energy and current in a circuit (b) Relate to rope loop where the teacher pulls the rope around and a student holds rope

between fingers. The student's hands get hot, energy is transferred from teacher to student due

to a current.

(c) Model the electric circuit as a pump lifting water up, which then flows down a channel,

turning a water wheel, only to be lifted up again. Where is energy put in and taken out? The

current is the flow of water.

(d) Think of a bicycle upside down - it doesn’t take much effort to make the wheels go around

fast. Current is the speed of the chain and in this case it is high but the energy transferred is

low.









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KS3

Recall that adding more components (a) Using a rope loop, pull through one student's fingers and note that the student experiences

to a series circuit makes bulbs heat. Then introduce a second student doing the same and note that if the teacher pulls with

(!brighter or !) dimmer same force the rope is slowed down and neither student experiences the same initial amount of

heat, i.e. energy has been shared.

(b) Demonstrate that adding more bulbs into a series circuit means that each bulb becomes

less bright.

(c) Relate to sharing out a fixed amount of a quanity so if there are more people to share to they

recieve less each, and that using this analogy, in sharing the energy from the battery,the more

bulbs there are, the less energy each bulb gets, so each is dimmer.

Recognise that thinner wire adversely (a) Relate resistance to students moving through a narrow corridor: if it is too narrow the flow

affects the brightness of bulbs slows down and the students get hot and bothered. The current drops and less energy is

available for the bulb.

(b) Demonstrate a simple circuit that includes a bulb and a nichrome wire link. A thinner wire

will glow hot and the bulb will dim.

Can identify resistance as a term that (a) Relate to rope loop. If a student lets a rope be pulled through their fingers they will

means opposing the flow of electricity experience heat. If the rope is gripped tighter they give more resistance and the rope slows.

(b) Students investigate fuse wire. What is it used for and how does it work?

(c) Identify 'resistance' as a key word and ask students to recall its definition as a term that

means opposing the flow of electricity. Draw linguistic connection between 'resistance' and

'resist', to put up a fight.

(d) Discuss students' experiences of dimmer switches. How do they think they work?



Know that increasing the number of (a) Working in small groups, students investigate the effect of adding more cells in a simple

cells or batteries in a circuit can make circuit.

bulbs shine more brightly (b) Relate to workers in a factory: if they get paid twice as much they work twice as hard! How

does this compare with electrical circuits?

(c) Consider the similarities between a power pack and a battery of cells. Draw a table of

similarities and differences.

Know that cells need to be connected (a) Students look at different shapes and sizes of batteries. Consider what features they have in

in correct polarity to work common, emphasising the positive and negative.

(b) Demonstrate a simple circuit that includes a battery of cells. Students predict then test the

effect of reversing the polarity of one or more of the cells.

(c) Relate to a toy car that will not work if the batteries are not inserted correctly.

Know that the voltage of a cell is a (a) Demonstrate using a power pack connected to a bulb. Discuss the effect on the bulb as the

measure of the energy available to dial is turned up from 3V to 6V. The bulb gives out more energy as voltage increased.

the circuit. (b) Rub a ruler with a tie and try to pick up paper circles due to the static force. The paper will

jump higher if the ruler has more voltage.

(c) Demonstrate how a voltmeter measures the energy difference between two points in a

circuit. Students predict how a voltmeter is connected into a circuit.



Know that the voltage of a circuit's (a) Relate a simple circuit to a rope loop pulled by a teacher. If the rope is pulled with more

energy source affects the current and force, the rope moves faster, corresponding to a larger voltage and a larger current. A student

performance of components lightly holding the rope will experience more heat as the voltage and current increase.

(qualitative) (b) Students investigate current readings on an ammeter in a simple circuit including a bulb as

voltage of power pack is varied.

(c) Think of riding a bicycle. When you pedal faster (increase voltage) the chain turns quicker

(increase current) and the bike goes faster (better performance).





7K Forces and their effects

QCA sub-objective Suggested action SPT relevant slide

Understand simple balanced and (a) To overcome the 'I can't see a force so it isnt there' misconception use cardboard arrows of

unbalanced forces (in linear different length and stick them to everyday objects. Emphasise that there are forces on static

movement) objects but they always cancel each other out.

(b) Students to make a weighing machine using an elastic band which they have calibrated with

hanging weights

Understand unbalanced forces in (a) That moving things need a force to keep them going is a very common misconception. Try

terms of newtons of force needed to to engage in thought experiments where students describe the motion of, for example, dropping

move objects a spanner out of a spaceship. Consider the effort needed to push and obect from rest and the

effort needed to keep the object moving

(b) Use cardboard arrows on a OHP to overlay on acetates of objects. Discuss the size of the

arrows when a objects are moved. Students may well introduce gravity and this may present

opprotunities to introduce reaction forces

(c) Produce a force ladder where the size of various forces is presented on a scale. Introduce a

Newton as the weight of an apple

Understand friction as a force that (a) Some students seem to think that friction only occurs when an object is moving or when it is

opposes motion stationary. Emphasise friction is present whenever two surfaces are in contact and that it

opposes motion

(b) Use a trainer or a book on a ramp and a newtonmeter, to investigate: 'How much force

needed to move the trainer' and ' What angle does the trainer first move'

(c) Draw the forces on a cyclist when he is cycling, coasting, and applying the brakes

Identify where friction can be useful (a) Discuss with students what it would be like to live in a frictionless world. Draw a cartoon of

(examples) the 'Adventures of the Child without Fiction!'

(b) Compare types of bicycle tyre. Consider why broader tyres give more grip and when they

are useful

(c) Show a video clip of race cars crashing especially when they lose grip at a corner. Write a

statement using the word 'friction' explaining why the cars crash. The car needs to experience

friction or else it will continue in a straight line.

Identify where friction can be a (a) Show video clips of Winter Olymics. Discuss why most events try very hard to reduce

problem (examples) friction. Students to select a sport and explain in detail why it is important to minimise friction

(b) Discuss with the students their experiences when friction has been a problem eg trying to

slide wonky windows or doors, or opening doors on creaky hinges

(c) Many students have a problem understanding air resistance, believing air is 'nothing'. Use a

pea-shooter to fire at a wall and consider how air can cause a considerable resistance

(consider air to be hitting moving objects like millions of tiny pea-shooters)









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KS3

Recognise some key effects of (a) Get the students to rub a finger really fast on a desk and note the heat generated. Now

contact friction (heat and wear) and repeat but lubricate with a drop of olive oil and compare the feeling.

recognise that a lubricant such as oil (b) Show containers of engine oil and discuss why a car will grind to a stop if it runs out of oil

can reduce it (c) Demonstrate the effect of rubbing 2 stones together, or sandpaper on wood, then the effect

of introducing water or oil between the surfaces.



Can read graphs showing direct (a) It is important that students have practice both plotting and using graphs. Produce a

relationships, e.g. force required to conversion table showing a direct relationship, plot the graph correctly and then use the graph

move objects across different to find an unknown value

surfaces (b) Students to make bar charts of a prepared table showing weights and ages of students in a

school. The students should write their own conclusions and enourage discussion about general

trends and linear relationships

Can read graphs showing inverse (a) It is important that students have practice both plotting and using graphs. Produce a

relationships e.g. less pulling force conversion table showing an indirect relationship eg weight of an object and distance from

indicates more effective lubricant Earth, plot the graph correctly and then use the graph to find an unknown value

(b) Use a card game to match graph shapes with their corresponding statement eg match an

inverse graph shape to a statement about pulling force and amount of lubrication. Discuss the

answers in detail so that students can relate a graph to visualisation.

Can resolve two unbalanced forces in (a) Great care must be taken when drawing force arrows onto objects. Make sure that they are

terms of resultant force and direction consistently straight, in proportion to the size of the force and the base of the arrow originates

from the object. Relate to drawings of real life situations such as a mass on a spring and draw

on an arrow for each of the forces that the mass is experiencing. Many students will intuitively

know the resultant force will be the vector sum of arrows if they see the force arrow drawings

(b) As above but some students may prefer a mathematical approach by giving arrow pointing

to the left a negative sign and the arrows to the left a positive sign as that the numbers can be

'added' to give resultant.



Can resolve three unbalanced forces (a) Use a tough rubber ring and combinations of students pulling from different sides. Discuss

in terms of resultant force and which students were the strongest and how we could tell from the direction the ring was pulled.

direction Practice drawing the force arrows on the ring in different situations and consider the resultant

force in each case.

(b) Consider bubbles rising in a bottle of fizzy drink. State that their are three forces acting on

each bubble, namely weight, upthrust and drag. Student to draw correct force arrow diagram for

the bubble.

Identify gravity as a force and its (a) Find a strong beam in the school and challenge students to dangle for as long as they can

effect from the beam. Let them feel the force of gravity, discuss the resultant forces acting and

whether or not they all feel the same force of gravity as each other? (No, they are different

weights!). The main purpose of this activity is to focus on the everyday phenomemon of gravity

and that the study of science is about real life, it also gets the students involved and so provides

a reference for later discussion

(b) Show animations of the revolving solar system and ask what is the force keeping it all

together? Most will state 'gravity' but in which direction does it act?

Identify upthrust as a force and its (a) Students to measure the weight of an object with a newtonmeter in air and in water.

effect Challenge the students to conclude for themselves that there must be an upthrust and to

calculate its magnitude

(b) Demonstrate to the students lowering a mass into a beaker of water that is placed on a top

pan balance. The mass is to be hanging from a newtonmeter. Challenge the pupils to declare

whether the reading on the balance will increase, decrease of stay the same. Discuss the

results in terms of forces.

(c) Students to push a balloon or polystyrene brick/flotation device into a bucket of water so that

they can feel the effect of upthrust for themselves. Relate upthrust to the feeling of being

supported in water when they go swimming or float.

Can calculate simple balanced forces (a) Consider a ship floating on water. Ask questions such as 'Does the ship still have weight?',

in floating and sinking 'Why isn't it sinking?', and 'Can we explain what we know with force arrows?'.

(b) Use an OHP and an acetate of a floating object. Students to come up and select the

appropriate cardboard arrows to represent weight and upthrust of the object. Discuss what the

resultant force would be.

Can calculate unbalanced forces in ( a) Demonstrate a helium balloon floating to the ceiling. Use cardboard force arrows on a

floating and sinking picture of a balloon to show that upthrust is bigger than its weight. When the balloon is released

which force will cause it to move and in what direction?

(b) Spend some time examining the keyword 'floating', concluding that unlike 'sinking' floating

can means staying at the same level as well as moving in the air. Emphasise that care must be

used when using common words when explaining the forces and motion of objects.



Understand that when an object floats (a) Consider a ship floating on water. Ask questions such as 'Does the ship still have weight?',

its weight is equal to the upthrust of 'Why isn't it sinking?', and 'Can we explain what we know with force arrows?'.

the fluid (b) Use an OHP and an acetate of a floating object. Students to come up and select the

appropriate cardboard arrows to represent weight and upthrust of the object. Discuss what the

resultant force would be.

Understand that when an object sinks (a) Density is a difficult concept and many students will believe 'heavy thing sink and light things

its density is more than the density of float'. Help to overcome this by letting the students feel a metal coin and a large wooden block,

the fluid comparing the weights. Drop both objects in water and make sure the students verbalise their

own conclusion. Ensure they establish some heavy objects float and attempt to relate to a

concept of density

(b) A practical investigation could be made into density by measuring the volume of a object by

the amount of water it displaces when pushed under water. Then dividing the mass of the object

by this volume and comparing results. Floating objects should have a density less than 1g/cm3.



Understand the concept of density (a) Be clear with the units that density is measured in, and show that the density of water can

and can apply to specific situations either be written as 1g/cm3 or 1000g/litres or 1000kg/m3 - its all the same! Students may have

problems changing units, commonly believing that there are 1000 cm3 in a m3.

(b) Show a large cylinder of water that has a density gradient (possibily using lots of bath salts

and allowing to settle). Squirt ink into the cylinder and find where if finds its level. Conclude that

the density of the ink lies between that of the salty water above and the salty water below.

Relate to smoke on a still day and clouds that flatten out at a certain height.









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State that the greater the applied (a) Show pictures of bungee jumping and ask for students experiences. Consider why there is a

force on a material the more it maximum weight allowance for bungee jumping

stretches (up to a limit) (b) Using all the necessary safety considerations, allow the students to heat the middle of a

glass rod in a fierce bunsen flame. Pull the ends of the rod apart and the students will produce

fine threads of glass

Can interpret tabular data on force (a) Use a cola lace (as from the sweet shop) or horse hair in an investigation to measure the

and extension extension with varying load. Tabulate results and them to use their tables to predict the

extension caused by an unused load

(b) Distinguish between 'length' and 'extension' by using two columns in a table

Can interpret force/extension graphs (a) Make a weighing machine using an elastic band, metre ruler, and hanging weights. Plot a

graph of results and then use the graph to predict the weight of an unknown object, then test the

prediction.

(b) Plot force/extension graphs from cola laces at different temperatures and ask students to

conclude the effect of temperature of the properties of the cola lace.

Recognise mass as a measure of (a) Concept map using various cards such as: 'Moon', 'Earth', 'Gravity', 'Mass', 'Weight', 'Force',

how much matter there is in an object 'Down', 'kg', 'Newton', '10N/kg'. Ask the students to draw links between their cards and explain

their choices

(b) Spend time explaining why a 'weight of 90kg' is not a correct science statement although it

is common in everyday life. Encourage students to switch between everyday and science

mode. State that 'mass is a measure of how much stuff there is and is measured in kilograms'.

Ask if that would change if the object went into space

Can state that weight is caused by (a) Prepare some cereal packets so that they have different weights but look identical. Let the

the force of gravity acting upon a students lift them and state that this what the packets would feel like on different planets which

mass have different gravities. What would they feel like in space?

(b) Show video footage (eg BBC Class Clips) of simulated zero gravity by free falling in a diving

aeroplane. The passengers are not really weightless but dont feel heavy. Discuss the forces on

a falling person and establish that their weight is constant throughout the fall.



Recall that gravity on Earth has a (a) Prepare some cereal packets so that they have different weights but look identical. Label

force of 10N and uses this in weight each with a big sticker that names the planet they represent. Make sure that the mass is visable

calculations but let students weigh them using a newtonmeter. Make the packet that has the Earth sticker

weigh ten times the mass (in kilograms).

(b) Students draw on forces arrows onto pictures of objects with the mass written next to the

object

Understand that mass does not (a) Prepare 3 cereal packets, looking the same but with different weights inside. One of them is

change but weight does in the context labelled Earth. Establish that gravity on the moon is 1/6 that on earth: which of the other 2

of the moon packets represents how the Earth packet would feel on the moon?

(b) Show a passage of text relating to the experiences of an astronaut. Set questions comparing

his weight on the Moon and Earth eg Why did he have to wear heavy boots on the Moon?

(c) Show video clip of life in a spaceship. Students to write a commentary highlighting the

features that are different compared to life on Earth



Describe what is meant by speed (a) 'Speed' is a common word that also has a particular science meaning. Ask students to list as

many words as they can that include the word 'speed' (eg: Speeding, Speedo, Speedway)

within a time limit, perhaps run as a competition. Discuss the science use of the word 'speed' as

the distance travelled in a certain time.

(b) Sort cards of objects (eg rabbit, skier, hurricane) into 'speeds'. This helps to appreciate

relative scale of speed rather than just accepting some objects are 'fast'.

Recognise the scientific units of (a) There is often confusion with different units used for speed. Show pictures of road signs in

speed the UK and in Europe and ask what they mean. Pay particular attention to the units quoted and

if necessary draw and an analogy with different measurements for height. Further work could

also discuss why some units are more appropriate than others (eg miles per hour for cars and

metres per second in classroom activities

(b) Issue the students with a conversion chart of metres/second to miles per hour and convert

roadsigns to metres/second. Also speeds with different units could be presented to the students

and then challenge them to find the fastest

(c) Card matching activity of objects (and animals) to their top speed. Emphasise the unit when

going through the answers which will lead to the idea that speed in a measured quantity.



Can calculate speed (a) Watch short video clips of moving objects such as windsurfer, bobsleigh, tortoise. Issue

students with stopclocks and ask them to calculate speed. This should open up discussion

about the required distances needed to calculate speed and possibly even a comparison of

different units

(b) Consider Police Speedtraps. Do students think they are useful? Now consider how they

work and try to get students to work it out for themselves using open questioning (speed is

calculated using markings on the road)

(c) Take the students out in the playground, place them at known distances, and issue each

with a stopclock. On a signal, everyone is to start their stopclock and a student starts to run.

The timers stop their clock when the runner passes by. Record the class results and plot

graphs.

Can calculate distance, given (a) Relate average speed to to typical journey where speeds vary. This helps to dispel the idea

average speed and time taken that a speed is always constant through a journey

(b) Many pupils will have low confidence in rearranging the speed equation. For these, try to

teach by using sentences about proportion eg If I am moving at 10 m/s, I travel 10 metres in

each second. How far do I travel in 2 seconds? etc

(c) Circus of toys, trollies, paper helicopters etc. Students to work out ranking of speeds even

though distances vary. Discuss how far they would travel in a given time before using maths to

confirm.

Can calculate journey time, given (a) Calculate the average speeds of cars travelling between two points along the road. Assume

average speed and distance that they keep that speed and discuss how far they would take to travel 2 km and then confirm

using maths

(b) Use motion analysis software to predict journey times. An example of suitable free software

can be downloaded from http://webphysics.nhctc.edu/vidshell/vidshell.html



7L The solar system and beyond

QCA sub-objective Suggested action SPT relevent slide:









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Know that the Sun appears to rise in a) Present students with a true/false worksheet that poses questions such as: At night time the

the East and set in the West Sun is covered by clouds, T / F ? Promote discussion within groups of students, perhaps using

a triad activity

b) Establish which way is north, west and east perhaps by relating N/S/E/W to maps of local

area/home/school. Students to write on paper where the Sun rises, where it sets and where it is

at midday. Also establish what happens differently during the summer and winter;



Know that the Earth takes one year to a) To discover student's initial conceptions, ask students to work in pairs. One of them is the

orbit the Sun Earth and is write instructions for how the Sun should move throughout the course of a year and

the other student is the Sun and should write instructions on how the Earth should move

throughout a year. Ask them to face each other and act on the instructions for each month;

b) Relate to information about the orbit time of other planets and hence deduce the lenth of a

'year' on other planets.



Understand the phenomena of night a) Position a globe (preferably on a titlted stand) near a light source in a dark room. Show the

and day countries and spin the globe emphasising which countries are experiencing night or day

b) Question students to relate any experiences they have of the night being at different times in

differnt countries (eg 24 hour time zones, long-haul flights, jet lag, sporting events, reality game

shows)

c) Use diagnostic questions to pinpoint student misconceptions. Common misconceptions are

that the Sun is covered by clouds at night, that the Sun goes round the Earth once a day and

that the Earth goes around the Sun once a day.



Recognise that the tilt of the Earth a) Position a light source in the middle of a large room and introduce a globe, emphasising that

remains constant as the Earth orbits the axis will always point to one corner of the room. Move the globe to the other side of the

the Sun during one year light, keeping the axis pointing at the same corner. Ask the students to relate amount of

sunshine to months of the year.

(b) Show long exposure photographs of nightime sky and of weather systems. Discuss whether

or not this evidence that the Earth is spinning.

Can name luminous and non- (a) List some shiney objects and consider it they could be seen at night time.

luminous sources in space (b) Relate experiences of total darkness (eg in caves) and conclude that even shiney object

could not be seen if it was really dark (not even cats could see!)

(c) List some objects in space and decide which ones are hot enough to give off their own light

(ie they are 'luminous') and which just reflect light.

Can use the words luminous or non- a) Discuss the following observations and argue whether they support the idea that the Moon is

luminous in context luminous or non-luminous: the moon cannot be seen during the day; not all the moon is visible;

men have landed on the moon; it is possible to read in moonlight etc;

(b) Consider where the word 'luminous' has been met before. Note that 'glow-in-the-dark' toys

and watch hands are luminous because they give off their own light but a mirror-ball is non-

luminous because it reflects light

Know that the Moon orbits the Earth (a) Show animation of Moon orbiting Earth and ask students whether they agree with this

every 28 days model, and if they do, ask how long do they think the moon takes to go around once.

Can identify simple phases of the a) Position a light source in the corner of a dark room. Ask a student to hold up a ball and

Moon, full, new and quarter-disc describe what they see from their view point. They are to rotate on the spot, describing what

they can see every quarter turn;

b) Students to rearrange pictures of the phases of the moon into the correct order;

Can describe a partial solar eclipse (a) Show a video clip of a solar eclipse. Discuss student ideas as to the cause of such of a

from Earth phenomenon and then ask students to model with balls.

(b) Consider the question: ' Why are solar eclipses rare?' because many students will think they

should occur every month. The answer to this comes from an appreciation of scale and it is

worth modelling with the Earth as a football, the moon as a tennis ball, and positioning them 6

metres apart. The angle of the plane of the Moon varies and rarely is in line.



Know that a total solar eclipse is (a) Model the Earth and Moon by using a football and a tennis ball and a light source as the

sunlight blocked by the Moon Sun. Draw attention to the remarkable coincidnce that the Moon and Sun appear to be the same

size from Earth and that when they all align at is possible to get a total eclipse from some parts

of Earth.

(b) Show a video clip of the last total eclipse in 1999, simultaneously modelling the alignment

(c) Ask students to explain a partial eclipse in their own words, comparing to a total eclipse





Understand how the phases of the a) Position a light source in the corner of a dark room. Ask a student to hold up a ball at arms

Moon make the Moon appear to length in the light. The student holding the ball describes what they see from their view point.

change shape from Earth They are to rotate on the spot, describing what they can see every quarter turn;

b) Show photograph of the Earth from the Moon. Discuss whether phases of the Earth would be

seen from the Moon.

c) Use diagnostic questioning to highlight student misconceptions. The common

misconceptions regarding the question 'Why does the moon change?' are that the moon's

appearance is due to: the shadow of the Earth, clouds covering the Moon, the shadow of a

planet on the Moon



Knows that a lunar eclipse is when (a) Model the Earth and Moon by using a football and a tennis ball and a light source as the

the Earth blocks sunlight to the Moon Sun. Discuss what the moon would look like as it moves into the shadow of the Earth

(b) Show a video clip of a lunar eclipse, simultaneously modelling with balls. Emphasise that

this is rare event because the angle of the plane of the Moon through the Earth varies.



Know that the Sun appears lower in (a) Relate to pictures showing shadows during the summer and the winte. Model shadow length

the sky in winter than in summer using a lamp and a toy figure, showing that shadow length is longer when the Sun is lower in

the sky.

(b) Discuss where the Sun is in a winter sky compared to a hot summer day.

Understand that the tilt of the Earth as a) Position a light source in the middle of a large room and introduce a globe, emphasising that

it orbits the Sun makes days in the the axis will always point to one corner of the room. Rotate the globe on its axis and highlight

UK longer or shorter when a particular country is in day and in night. Move the globe to the other side of the light,

keeping the axis pointing at the same corner. Again rotate the globe about its axis and ask

students to now descibe the day and night time. Discuss the corresponding months of the year

and how in summer months we have longer days and shorter nights

b) Model using a tilted Earth and a light source. Use a ruler parallel to the light rays that hit the

Earth and ask students to describe why the Sun is never completely up overhead in the UK









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Can relate the position of the Sun or a) Position a light source in the middle of a large room and introduce a globe, emphasising that

the Earth to the changing height of the axis will always point to one corner of the room. Move the globe to the other side of the

the Sun in the sky light, keeping the axis pointing at the same corner. Use a ruler parallel to the rays from the Sun

to show angle is greater during summer;

b) As above, but also translate hoe the Sun would look in the sky as the Earth spins on its axis.



Know that the tilt of the Earth gives us (a) Ask students to brainstorm all the differences between summer and winter. Pull out

changing seasons temperature, daylength, height of sun in sky. Draw anecdotes about it being winter in Australia

when it is summer in the UK. Pool student reasons why we get seasons.

(b) Use an overhead projector and an acetate with dark bars across it. Put a globe with tilted

axis into the light and note that the bright bars are more spread out towards the poles i.e.

energy covers a large area. Rotate the globe so that the axis is now pointing at a different

corner of the room and discuss the difference this has made to any particular country.

(c) Produce posters of the seasons we would experience if the Earth had a different angle of tilt

(eg if tilt angle = 0)



Understand that the tilt of the Earth a) Highlight that 'spin', 'orbit', 'rotate', 'revolve' are words with similar meaning and that they may

gives us the four seasons (on level of be a source of confusion. 'Spin' is about an axis and 'Orbit' is about a body. Agree with students

longer days heating area for longer) what is meant by each word.

b) Use diagnostic questioning to highlight student misconceptions about seasons. The common

misconceptions about seasons are: clouds stop heat from the Sun, the Sun gets closer to the

Earth, and in the summer, the Sun is on 'our side'.

Understand why the tilt of the Earth a) Lift hands up to feel the heat from a fire. Most heat is felt when palms are perpendicular to

gives us the four seasons rays. Relate to winter when the Sun is low (fingers pointing at fire) and colder days. Similarly,

when the Sun is more overhead the palms get more direct rays;

b) Confront misconceptions about the Earth getting closer to the Sun during the summer by

discussing experiences of an Australian Christmas or reality game shows or sporting events;



Recall that our solar system consists a) Concept mapping in groups three or four. Students to link 'concept' cards displaying terms

of our Sun, planets, asteroids and such as planet, sun, star, gravity, meteorite, orbit, rotate, etc into a poster and discuss why they

natural satellites that orbit the planets have made their links

and can describe how they behave b) Produce a leaflet 'Guide to the Solar System' showing the names, positions and

characteristics of the different bodies

Know the order of the first four a) Write a travel brochure for space tourists. What would it be like to go on a criuse to the Inner

planets nearest the Sun Planets and how long would it take to reach each destination?

b) Discuss how astronomers obtain evidence of planets and other bodies in the solar system by

using telescopes but before only the closest planets could be seen with the naked eye. Relate

planets to Roman and Greek mythologies

c) Create wall display of the four inner planets with groups of students taking responsibilty fro

drawing and describing their planet (d) Devise a useful mnuemonic such as Mean Vegatables

Eat Man! to remember the four inner planets

Know the correct order of all the a) Model solar system using fruit. Nine pupils hold cards showing the planet they represent and

planets use a pumpkin for Jupiter and a pea for Pluto

b) Devise a mnuemonic such as My Very Eccentric Mate Jumps Suddenly Up Near Policemen

to order planets, and then draw a cartoon of their mnuemonic;

Know that conditions on a planet (ie a) Use planetary data, that is commonly available from textbooks or the internet, to produce

hot/cold) depend mostly on its graphs or charts that show trend of surface temperature against distance from Sun (Venus is

distance from the Sun exceptional)

b) Present students with a spreadsheet containing planetary information such as: , distance

from the Sun, length of year, length of day and sort data to produce a graphical representation

of trends

Know that the planets take different a) Use planetary data, that is commonly available from textbooks or the internet, to produce

times to orbit the Sun, depending on graphs or charts that show trend of orbit time against distance from Sun;

distance b) Take students onto a playground or field. Instruct them to to lap around a centre point at

differnt radii and ask them why planets take differnt times to orbit the Sun

Know that the brightest stars are a) Show some pictures of constellations such as Orion and The Plough. Note that sometimes

closest to Earth these stars are accompanied by another wandering star and seems to move from one

constellation to another. Explain that the wandering star is not actually a star at all but a planet.

Ask how can a planet look like a star and relate to luminous/non-luminous objects.

b) Use a card sort game to order in size: an asteroid, a planet, a star, a solar system, a galaxy,

a universe.

c) Show some images of galaxies and nebula and note that some stars are brighter than others

because they are bigger and sometimes stars look dimmer because they are so far away





Have some understanding of the a) Model solar system along a corridor. Students to cut out circular discs to scale of the first

distances between objects in our four planets and label;

solar system b) Show 'Powers of Ten' video clip (available from the internet)

c) Write a travel brochure for space tourists. What would it be like to go on a criuse to the

Wonders of the Solar System and how long would it take to reach each destination? (a useful

resource is Bill Bryson's 'A brief History of Everything')

Understand that a light year is a a) Emphasise that a light year is used as a measurement of distance not time and that nothing,

measurement of distance not time according to Einstein, can travel faster than light

b) Students are often fascinated by large numbers. To travel around the world is about 36 000

km, to the moon is about 15 000 000 km and to the nearest star is about 40 000 000 000 km.

Calculate how long it would take to travel theses distances in a spacecraft travelling at 50 000

km/hr.

c) Set students to calculate the number of times light travels around the Earth in each second

d) State that when we look at our nearest star we are look back 70 years in time and ask

students to explain that statement





Unit 8I Heating and cooling

QCA sub-objective Suggested action SPT relevent slides









Page 8 Based on QCA objectives

KS3

Know about the Celsius scale of (a) Feel warmth of water and measure using thermometer; suggest temperatures and compare.

temperature used in science (b) Discuss holidays and typical temperatures that students would have experienced or would

have heard on weather reports. Mention negative temperatures and ask what is the coldest

temperature they have experienced.

(c) Highlight the symbol oC as meaning 'degrees Celsius' and ask if they have heard of any

other temperature scales. State that 'degrees Centigrade' is the same as 'degrees Celsius' and

ask it anybody has heard of 'degrees Fahrenheit'.



Know some typical temperatures and (a) Measure the temperature of ice and boiling water using a Celsius thermometer and plot on a

the freezing point and boiling point of large visible scale. Ask the students to use thermometers to measure the temperature of the air

water inside and outside the classroom, the temperature of their hand and the temperature of a nice

cup of tea. Plot these values on the scale.

(b) Research the hottest and coldest places on Earth and display on a world map.

(c) Challenge students to explain why, on holiday, the temperature was over 'a hundred

degrees!' but the water in my body didn’t boil. The answer, of course, is that two different

temperature scales are used (boiling point in the Fahrenheit scale is 212 degrees). Relate key

temperatures (freezing and boiling points of water, room temperature and body temperature)

between Celsius and Fahrenheit scales.

Know that there are different kinds of (a) Demonstrate different types of thermometer, especially show the common glass/alcohol and

thermometer compare with a temperature probe. Show that they record the same temperature for a cup of

tea and consider the advantages and disadvantages of each.

(b) Show pictures of hot furnaces and consider why a typical glass thermometer would not be

suitable. Similarly think of the problems in recording a large number of temperatures over a

long period of time, especially when the person doesnt want to sit there all day and night

recording the temperatures in a book. In these cases, other kinds of thermometer have to be

used.

(c) Demonstrate a thermocouple connected to a suitable ammeter. Use this to show what is

meant by the key word 'calibration', ie it is possible to use any quantity that varies with

temperature as a thermometer as long as it is consistent.

Know that temperature is a measure (a) 'Temperature' is a measure of the average movement energy of particles. Imagine people

of how hot things are. shopping in a supermarket - some people potter around and others whizz around as quickly as

they can. 'Temperature' is like a measure of their average speed - it doesn't measure how many

people are in the supermarket. Whereas 'heat' is a measure of the number of people times the

average speed, ie the total energy.

(b) Still using the supermarket analogy, there are times of the day when people come home

from work and lots of them just want to get the shopping done as quickly as possible and go

home. In this case the average speed goes up. If the average speed of particles increases then

the thing is hotter and the temperature is higher.

(c) Role play air particles on a cold day. Here the students walk slowly in straight lines in an

enclosed space, bouncing off the walls and each other. Instruct them that the temperature is

getting even colder and that they should walk even slower. Eventually, it gets so cold that they

stop - this represents temperature of Absolute Zero (-273oC), the temperature of deep space.



know the difference between heat (a) Consider a sparkler and a cold bath. Ask if it sparkler were put out in the bath, whether the

and temperature temperature of the water would be hot enough to bathe in? The answer is 'no', because the bath

has many more particles and so the energy has to be shared around so much that it hardly

makes any difference.

(b) Similarly, consider a hot bath and a sparkler - which has more total energy? Its the bath

because, although the sparker is made up of bits of white hot metal, there are so few particles

compared to a bath (actually even a cold bath of water has considerably more total energy than

a hot sparkler).

(c) Role play air particles on a cold day. Here the students walk slowly in straight lines in an

enclosed(!) space, bouncing off the walls and each other. Gradually let more and more people

become involved with the role play. A constant temperature means that they all walk around

slowly, no matter how many people, but the total energy goes up because everybody who joins

the game brings their own energy along.

recognise heat as energy. (a) In groups, ask students to write down as many expressions as they can that include the

word 'energy' on postiks and then try to organise their expressions into groups with common

features. Use this work as a basis to explain that in science, everyday words often don't help

understanding. It is useful to think of energy as 'the ability to do something' (and, importantly, it

is possible to quantify energy, eg. this object has twice as much energy as this one).

(b) Many students believe that heat is a substance, reinforced by expressions such as 'heat

rises' or 'don't let the heat out!'. Consider expresssions involving the word 'heat' and ask the

students to define what they actually mean by 'heat'. State that in science it is possible 'to heat

something' and that 'heat' is also used as a measure of the amount of energy an object has.

(c) Consider the expression 'the flame has heat' with the students and try to rewrite this in terms

of particle movement eg. 'the partcles near the flame are moving faster'





know that temperature change (a) The word 'heat' is common in every day use but its connotations are varied and often

involves energy flow misleading. Energy is stored in hot bodies and this energy can be shifted to other stores, but

energy is energy and there aren't different types of energy. Introduce this idea to students,

asking them to list, instead of types of energy, ways in which energy can be stored up 'waiting'

to be used.

(b) Introduce a 'thermal store', and a 'chemical store' as ways of storing energy - consider when

a match burns, before the match is struck energy is stored in a 'chemical store', afterwards the

air has more stored energy (more particles are moving faster) - we say the air has more energy

stored in its 'thermal store'.

(c) Role play particles in air on a cold day, where the students walk in random directions in

straight lines, bouncing off each other and the walls. One student hides behind a chair and

represents the Sun. As the Sun appears the particles move faster and as it goes away they

slow down again. The Sun is giving the particles energy via electromagnetic radiation (and the

particles lose their energy by warming the land and sea when they hit them)









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understand that heat flows as a result (a) Show histograms showing temperature against volume of water for two different samples.

of temperature differences. The area under the bar is an indication of heat energy. Mix the volumes of water and record the

resulting temperature. Investigate using different proportions of hot and cold, predicting what

the new temperature will be.

(b) Students often believe that if things are heated up for the same time, their temperature will

go up by the same amount. In fact the final temperature of an object depends on energy

supplied, mass and material. Design an investigation to find the factors that effect the final

temperature of an object.

(c) Imagine being at a crowded rock concert (like Glastonbury). People at the front start

bouncing up and down, knocking onto the people behind. The people at the front (high

temperature) get slowed down a bit because ethey keep hitting the people behind and the

people behind move a bit faster than they did - a kind of average is obtained. Explore this

analogy of temperature difference and energy transfer with students.

know that heat flows more easily (a) Touch different materials and discuss which ones feel hotter. Imagine putting your bare feet

through good thermal conductors on ceramic tiles and a woolen rug - which one feels warmer. Inform the students that the tiles

and the rug are at the same temperature - so why do they feel different? The answer is that the

tiles are better at moving the energy away from the body, so it loses energy quicker and feels

colder.

(b) Consider the keyword 'conductor'. In groups or pairs, students write down sentences that

include the word 'conductor'. Sort into scientific uses and others. Students will probably recall

electrical conductors from earlier work, but it is important that they appreciate that 'conductors'

let energy pass through them easily. Compare with lightning conductors and emphasise that

they let energy pass through them easily .

(c) Concentrate on the keyword 'thermal'. Brainstorm where the term is used (eg thermal

underwear, thermal springs, thermal gloves), concluding that it is an alternative to 'heat' in many

instances.

know that most metals are good (a) Discuss situations where students have touched metal when it has been a cold day. The

thermal conductors body temperature is higher than that of the metal and the metal moves the energy away very

quickly so it feels cold to the touch.

(b) Demonstrate the conductivity of metal rods compared to glass rods by putting them both in a

beaker of hot water and feeling the other ends of the rod. Pieces of thermal paper could be

stuck to the ends of the rods and the colour changes could be compared.

(c) Students to think of practical examples of why metals are used in certain situations. In

particular, the properties of mercury could be considered. Why is mercury used as a switch in

situations where the device has to be level eg in devices uded in surveying?

know that heat flows less easily (a) Discuss cooking utensils and, in particular, the reasons why a saucepan is metal but with a

through poor thermal conductors non-metal (wooden, Bakelite, etc.) handle. Suppose what would happen if it were the other way

around!

(b) Demonstrate temperature gradient along rods of different material, e.g. copper and steel.

This can be done by fixing drawing pins to the rods using blobs of petroleum jelly and heating

one end of the rods. As the energy travels down the rod the pins fall off, so giving an indication

of rate of travel. Use this demonstration to show that there is a range of values of conductivity -

from those that allow the energy to pass through very quickly to those that don't seem to allow

energy to pass through it at all.

(c) Recount situations where students have noticed the apparent difference in temperature

between materials eg. cermic tiles and woolen rugs or metal handlebars and rubber grips.

Emphasise that body temperature is higher than the objects and that they feel warm or cold

depending on the rate that energy is moved away from the body.

know that liquids and gases are poor (a) Demonstrate poor of conducitvity water using ice cube at bottom of a boiling tube which is

thermal conductors being strongly heated at the top. Temperature sensors could be used showing the difference in

temperature at top and bottom of the tube.

(b) Investigate double glazing or thermos flask. Students need to appreciate that there is air (or

partial vacuum) involved in keeping the room or drink warm and to develop reasons as to why

they work.

(c) Research highly effective clothing that is used in extreme weather conditions. Focus on air

pockets or water layers that are an integral part of their design.

know that poor thermal conductors (a) Brainstorm sentences which use the word 'insulation' or 'insultators'. Encourage students to

are called insulators write 3 sentences of their own that correctly use these words.

(b) Separate a box of materials into 'good thermal conductors' and 'poor thermal conductors'.

Introduce the word 'Insulators' as an alternative to 'poor thermal conductors'.

(c) Compare with electrical insulators, which is a term students may have come across

previously. Students to compare and contrast the similarities and differences between electrical

insulators and thermal insulators in their own words.

know that insulation can reduce (a) Discuss ways to reduce energy loss from a house. Include loft insulation, double glazing,

unwanted energy transfer carpets and wall paper. This is an opprtunity to assess if students have the misconception

summarised by 'Shut the door - you'll let the cold in'. Many students have felt cold draughts and

believe that The Cold is an entity that has to be prevented from coming in. Encourage students

to write in open prose by themselves and then try to emphasise that it is a matter of keeping a

place of high energy just that - a place of high energy.

(b) Investigate the effect an insulating material. Use a film cannister with hot water and a

temperature probe inserted through the lid. Wrap a thin layer of insulation around the cannister

and record the time to drop a certain temperature. Repeat with more and more layers and

compare.

(c) Challenge students to use everyday materials such as bubble wrap and cotton wool to keep

a hot object as warm for as long as possible. Make it into a competition - Who can keep my

soup warmest?



know that radiation energy can travel (a) To most students, the key word 'radiation' is linked with 'radioactivity' and to a lesser extent

through a vacuum 'radiators'. It is important that 'radiation' is assosociated with light and that there is a whole

spectrum (or colours) of light, most of which our eyes can not see!

(b) Heat strongly a wire gauze until it glows red hot. Watch it as it cools. Establish that objects

cool down by giving off radiation.

(c) Recall the energy can be transferred by particles but that there are no particles between the

Sun and the Earth. Challenge the students to expain why the sun warms us up.









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understand that hot fluids rise and (a) The sihouette of a candle flame or a bunsen burner flame in a bright light should show a

cool ones sink turbulent shadow rising upwards. A spiral 'snake' can be made to rotate if it is put in this

upstream of air. Establish that it is an image of moving air that is being seen not an image of

'heat'.

(b) Use computer images to establish what is meant by 'convection currents'. Establish that hot

material rises to be replaced by cooler material and circular currents are obtained in a closed

system. Relate to hang-gliding and convection currents in the Earth's mantle.

(c) Consider and research weather systems. Ask the students to explain why we get wind and

they could conjecture why there are ocean currents like the Gulf Stream. Here, differences in

global warming cause areas of hot fluid and areas of cold fluid, resulting in currents.



understand that expansion of a (a) Demonstrate a metal ball that can just pass through a hoop or gap at room temperature, but

material reduces density is unable to do so when hot. Consider the key word 'density'. Ask the students if there is any

more 'stuff' or matter given to the metal and establish that there is the same amount of matter it

is just more spread out. Students to describe this themselves using the word 'density'.

(b) Show ice cubes floating on top of a glass of water. Ask students to explain why the ice floats

using the expression 'density'. Consider why ice cubes have less density than water (ice

occupies more space for given mass compared to water).



know that materials can change state (a) A class practical where a beaker of ice is heated over a bunsen burner until it melts and

when energy is added or removed then boils should show clearly that a constant input of thermal energy causes a change of state.

Consider what would happen to steam and then water as energy is removed.

(b) Elicit ideas that cold days have less energy from the Sun and that is why we get ice and

snow.

(c) Heat a boiling tube of wax until it has melted, insert a temperature probe and alow to freeze.

Note the temperature fall and the students could write in their own words what is happening to

the wax in terms of its stored energy.



know that these changes are (a) Consider what is meant by the key expression 'reversible change' and establish that with a

reversible reversible change you can get back to exactly what you started with. Ask the students to come

up with some examples of non-reversible change (such as frying an egg, or striking a match)

and of reversible changes.

(b) Use ICT simulations to show the effects of heating on particles. Discuss what the effect will

be if the particles loose energy and try to expand the model to explain complications of non-

reversible changes (ie the partcles have reacted with each other).

(c) Research cryogenics. Establish the idea that living material can be frozen and then unfrozen

so that it is living again - do the students believethis is possible and what are the moral

implications?

know that changes of state occur at (a) Students to independently heat boiling tubes of wax, insert a temperature probe or

fixed temperatures. thermometer and record the freezing temperature. A comparison of different results should

show that the freezing temperature is same for everybody. It is worth establishing that freezing

temperature is the same as melting temperature, as students can think that these are different.

This can be demonstrated by now heating the boiling tube of wax again in a water bath and

comparing the melting temperature with others.

(b) Research melting/freezing points and boiling points of water at standard pressures of

different substances and plot them on a large scale. This can be an important exercise as many

students will have difficulty with negative numbers and they need to appreciate -200oC is colder

than -100oC for example.

(c) Students to consider the word 'evaporation' which, like boiling, converts liquid to vapour but

at a lower temperature.

understand that particles move further (a) Demonstrate expansion of air by placing sealed syringes in hot water or the expansion of

apart with increasing temperature liquid in a capillary tube as one end is warmed. Relate to simple thermometers and obtain

suggestions how the devise can be used to measure temperature. Ask the students to consider

particles and for their ideas as to what is happening to them as they are warmed.

(b) Show an ICT simulation of particle movement in fluids at differnt temperatures eg

http://www.walter-fendt.de/ph14e/



explain conduction using the particle (a) Role play conduction. Here, students for a conga line with both hands on the shoulders of

model the person in front to represent bonding in solids. As the person at one and pushes backwards

and forwards, the energy is transmitted down the line. Repeat but this time the students only

use one hand, representing liquid - they are then asked to explain why conduction is not as

good in liquids.

(b) Show an ICT simulation of partcle movement during conduction eg Institute of Physics'

Supporting Physics Teaching (11-14), Energy CD.

(c) Introduce to students that, in metals, conduction is also due to free electrons. How would

students model electron conduction using role play? For example, a ball could also be thrown

down the line.

explain convection in terms of the (a) Imagine a really busy concert or dense crowd of people. Now imagine a group of people

particle model getting more and boisterous and dancing about. Within the crowd there is a place where there

is more space between the people. This is meant to illustrate that in a crowd of gas particles,

ubbles or pockets of lower density are possible.

(b) Ask the students to push an air-filled balloon into a bucket of water and let them experience

the upthrust. Relate to a helium filled balloon and brainstorm why the balloon rises in air. Relate

now to a hot air balloon and ask for student ideas as to why it rises.

(c) Show pictures of hot-air balloons and ask students if anybody has experience in riding in

one. Ask what the heater does and how the pilot makes the balloon go up an down. The

students are to describe, in their own words or in pairs what is happing to the particles in the

balloon as it goes on a journey.

understand that movement of (a) Ask students how they would role play particle movement in gases to younger children. Ask

particles increases with increasing what would happen if they were given more energy and how that could be demonstrated.

temperature (b) Heat a conical flask that contains a little water. Then plug the opening with a pickled egg. As

the air inside cools, the particles more less slowly, and because some of the particles were

evacuated during heating there are less particle than before. The result is that the is an

imbalance of pressure inside and outside the flask and the egg gets pushed in. Students could

draw a cartoon strip of the various stages.









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be able to use the particle model to (a) Role play changes of state. Here the students put both hands on the shoulders of another

explain changes of state student to represent 'solid', one hand on a shoulder to represent 'liquid', and no hands to

represent 'gas'. Discuss the model with the students and how it could be improved to represent

ice turning into steam.

(b) Use an ICT computer simulation of particles movement during the three phases of matter

and ask students to identify the features that are different in each state.

(c) Research how changes of state are dependent of the surrounding pressure. Students to

explain, using particle theory, why you can never get a nice cup of tea on top of a mountain.





8J Magnets & electromagnets

QCA sub-objective Suggested action

Can state that a magnet attracts (a) Highlight that most everyday materials are a mixture of different elements. Show a Periodic

magnetic materials but not others Table and explain that this is a list of the different ingredients that we now about. Pick out iron

and state that this element is special because a magnet sticks to it! Use a magnet and a

sample of iron to show that it is magnetic. Issue a magnet to students and they investigate what

things contain iron

(b) Investigate objects that a fridge magnet will or will not stick to, including something like

copper pipes or silver jewellry (ie something that is metallic but not magnetic).

(c) Students to find magnets around their own home and say why they are useful, emphasing

the key words 'attract' and 'iron'

Is aware that magnets have 2 poles n (a) Look at different types of permanent magnet inc. bar magnet, horseshoe magnet, flat

& s: magnets. Let the students play with them - which ends stick together and which ends push

away? Try to push two repelling magnets together - who is the strongest person here? Ask how

is a bar magnet turned into a horseshoe magnet (by bending it around).

(b) Magnets have places where their 'magic' seems to be concentrated - these are called

'poles'. Pose the question ' What happens when a magnet is cut in half - does it have one pole

and one end without magnetism?'. Discuss their ideas and demonstrate if possible. Tell them

that even the greatest scientist that have ever lived have never found a pole on its own - they

always come in pairs.

(c) Show students compasses (especially walker's compasses) - what do they notice about

them? Where would compasses be useful? Show the effect of different ends of a magnet on a

compass needle.

Identifies which materials are (a) There is a very common misconception that all metals are magnetic. The classification of

magnetic materials into electrical conductors in primary school suggests to children that metals are

special when it comes to electricity. Therefore, it is not surprising that the same classification is

transferred in children’s thinking into the topic of magnetism. Metals are expected to be

magnetic and non-metals are expected to be non-magnetic. In fact, most metals are not

magnetic. The most common magnetic metals are iron, steels with a high iron content, nickel

and cobalt. Elicit the student's starting point by testing labelled substances.

(b) Get some samples of iron and pure copper. Which is magnetic? Now, investigate which

coins are magnetic. Conclude that new copper coins must contain iron (or some other magnetic

materials).

(c) Referring to the Periodic Table, find and take time to pronounce Iron, Nickel and Cobalt.

Indentify these as magnetic materials and that any substance that contains these will be

magnetic to some extent. Refer to the word 'steel' and explain that steels contain iron and so

are magnetic.



Knows that like poles repel & unlike (a) Explore a magnetic travel chess set. Which magnets are the same way up? This can be

poles attract tested by trying to push their bases together - some will stick together and some repel each

other. Students to write up their own conclusions.

(b) Suspend a bar magnet from a stirrup. Bring another magnet near, showing the effects of

different ends of the approaching magnet on the bar magnet. When is the magnet pushed

away? Repeat with a metal bar - note that it is not possible to make the magnet repel.

(c) Emphasise the key word 'repel', and practise using it in sentences to replace 'push away

from'. The sentence 'like poles repel but opposites attract' is a key one and students should be

encouraged to remember it, perhaps by using analogies with personalities.





the strongest part of a magnet is at (a) Cover a bar magnet in a thin clear plastic bag and dip into iron filings. Note that the majority

the poles of iron filings cluster at the ends.

(b) Place a bar magnet on an OHP and use plotting compasses to construct lines of force. The

lines of force are more concentrated at the poles which is indication of a stronger field in that

region and more force.

(c) Race some ball bearing along a table by using a strong magnet underneath to pull them

along. Ask the students what they did to make the balls move fastest, especially concentrating

on the orientation of the magnet.

Magnets can work in a vacuum (a) Some students believe magnets need air to work. Challenge this misconception by

demonstrating the effect of a magnet on a piece of iron that is inside a bell jar. Ask the students

to predict what will happen as air is evacuated from the flask and then demonstrate that air is

not needed for magnetism to work.

(b) The magnetic force requires no medium to act-at-a-distance. The concept of a field is quite

an advanced one and many students struggle with the idea that a force can be exerted without

something being in contact with it. Compare magnetic force with gravitational force, listing the

similarities and the big difference that it is possible to push something away with a magnet but

not with gravity. Emphasise the fundamental importance of this difference - nobody anywhere

ever has ever been able to work out why!

(c) Obtain data about magnetic fields of planets and how far their magnetism extends into

space. Point out that the magnetic fields do not depend on whether the planet has an

atmosphere or not.

States how magnetic materials can (a) Firstly demonstrate that a steel rod is not magnetic then rub the length of a steel rod

be made into magnets continuously and methodically with the same end of a magnet, taking care to only stroke the

magnet in one direction (a bit like stroking a cat!). Test the rod to see if it is magnetic.

(b) Place an steel rod in a solenoid (tunnel of wire coils) carrying a DC current. Test the rod to

see if it is magnetic.

(c) Repeat these procedures but use a soft iron rod instead on an steel one. The idea here is to

show that it is easier to make a magnet out of steel than soft iron because the steel seems

more capable of retaining the magnetism.









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Knows how magnets can be (a) A strong magnet (such as rare earth magnets which are now readily available) can be used

demagnetised to hold coins. Heat the magnet strongly and the coins will drop.

(b) Place a magnet in solenoid with AC current. Show that the magnet has lost its magnetism

after a short time in the solenoid.

(c) Get a magnet an hit it continually with a big hammer (usually there are no shortage of

volunteers). Show that the magnet soon loses its magnetism.

Magnetism is reduced when the (a) Many students feel that magnets do wear out because the magnets 'use up power' -

internal magnets in a material perhaps sending out 'magnetism' and eventually it all runs out. To gain an understanding of

become disordered demagnetism it is helpful to consider the magnet to be made up of internal mini-magnets. When

the mini-magnets are aligned the overall effect is a magnetic bar but when they become

disordered and out of alignment with each other, then effectively they cancel each other out. In

real life, ‘permanent’ magnets do wear and lose their magnetism this is because the mini

magnets gradual get out of alignment.

(b) Demonstrate the idea of mini magnets lining up by using as many small magnets as are

available. Discuss what the overall effect would be and compare to a situation where some of

the magnets are not lined up.

(c) Role play this idea by asking all of the students to point out of the window (hopefully they will

all point in the same direction) and then ask them to point to where the Headteacher is at the

moment - hopefully they will point in more random directions.

Knows that all magnetic materials (a) There is a common misconception that gravity is related to magnetism. Children know that

have a North seeking and a South magnets are associated with a magnetic force and that there is magnetism associated with the

seeking pole Earth. When a mechanism is sought to explain gravity, magnetism therefore becomes an

obvious candidate. Discuss the students' ideas with them and identify with them that gravity and

magnetism are fundamentally different types of force.

(b) Hang a bar magnet in a sling, taking care that there are not any magnetic materials near by

that it may be attracted to. Consider what direction the magnet is pointing and what would

happen if you kept on following the magnet north. Identify one end of a magnet as 'north-

seeking' and the other as 'south-seeking.

(c) Many students think that the Earth's magnet must be special because a north pole of a

compass is attracted to the North Pole of the Earth. Emphasise that the Earth's magnet is

‘upside down’ and that fundamentally unlike poles attract. It can be demonstrated that the North

pole of a walker's compass is attracted to the South pole of a bar magnet.



Recognises the shape of a magnetic (a) It is common to show the shape of a magnetic field using iron filings, however, a magnetic

field around a bar magnet field is a theoretical idea invented by physicists that is useful. There is nothing to see or touch

around the magnet. When pupils first come across the idea of a magnetic field it is not

surprising that many think the field is the iron filings they see. The magnetic field is the space

around the magnet where it will attract or repel and the shape is best shown by first placing a

bar magnet on a OHP and using a small plotting compass to gradually construct a 'line of force',

and then another, each time discussing what is happening

(b) Show that a magnetic field is in 3D space by using chopped iron wool in caster oil. The iron

pieces align to point towards a pole and it shows that the magnetic field is all around the

magnet not just flat on the paper.

(c) Compare the fields of two magnets repelling each other to two balloons being pushed

together. Emphasise that the magnetic fields try to restore their original shape and so push the

other magnet away.



Understands that the magnetic field (a) Use a force meter to measure how much force it takes to pull a bar magnet away from a

weakens over distance retort stand base. Investigate the effect of placing thin sheets of card between magnet and

base, concluding that the further the magnet is from the base , the easier it is to pull them apart.

The effect of the actual card as opposed to air in the gap is minimal.

(b) Use a magnet beneath an exercise book to magically move a metal object above. Challenge

the students to guess how many pages are needed before the trick no longer works and then

test it out.

(c) Carefully observe two attracting magnets at different distances. Note the movement gets

faster as the magnets get closer. Role play this observation.

Describes the function of an (a) Students sometimes believe that bar magnets are different from electromagnets and that it

electromagnet at a car recycling is a different kind of magnetism. Discuss student starting points and emphasise that permanent

plantcar crusher magnets and electromagnets give rise to the same kind of magnetic force. It doesn't matter how

a magnet is made, its magnetic properties are the same as another magnet.

(b) Use a BIG electromagnet to demonstrate how strong an electromagent can be. Gradually

add small weights at first and the kilograms at a time, amazing the students with just how much

wieght it is possible to hold.

(c) Demonstrate with an electromagnet that is suspending a load, the effect of cutting the

current. Discuss why this different to a bar magnet and where this ability to switch magnetism

on and off would be useful. Relate explicitly to a car crushing plant.



Recalls the use of electromagets in (a) Demonstrate an electric doorbell. Here, a springy strip of metal (eg a hacksaw blade) is

domestic electrical apparatusetc attracted to an electromagnet and one end hits a bell. It needs to be set up so that the strip is

part of the circuit, and by moving it breaks the circuit and springs back, only for it all to start

again. It is better if the students themsevlves construct this circuit and identify clearly each

stage as it works.

(b) Show students a modern 'fuse box', like they will have at home. Show the RCB switches that

will cut out the electricity to different pats of the building and make it clear that each switch

contains an electromagnet. Challenge students to explain how they work.

(c) Start with the statement ' Electromagnets are often used as a safe way to turn on dangerous

circuits' and let the students working in groups develop ideas. Would they dare to turn on a

switch in a live national grid with 100 000's volts? I wouldnt - I'd use an electromagnet, but

how? For example, a car has a start up current of 30A but a key is turned to complete a smaller

circuit, that activates a magnet, that in turn completes the 30A circuit.



Describes how to make an (a) Students to construct their own electromagnets using insulated wire and a power supply that

electromagnet gives a high current (eg Westminster Power Supplies). Take care not to use a steel former

instead of an iron one, because the steel former retains some of its magnetism when the current

is switched off - which is detrimental to the key points about electromagnets.

(b) Students to write an advertisng leaflet, explaining the key advantages of electromagnets,

where they could be used how they are made.

(c) Use internet resources to explore the commercial manufacture of electromagnets.









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Recognises that wires carrying (a) Demonstrate Oersted's experiment. The secret here is to generate some of the surprise and

current produce an electromagnetic interest that Oersted experienced when he witnessed this phenomenon. Place a plotting

field compass on an OHP and agree that it is pointing North-South. Bring a wire near and note that

nothing happens until a current of at least 5A is passed through the wire, when the compass will

change direction. Conclude that a current carrying wire must generate a magnetic field.

(b) A card with a loop of current carrying wire cutting perpendicularly across it is very much

worth investigating as plotting compasses show a circular magnetic field around the wire. Next

a card with a series of loops should show the magnetic field around a solenoid.

(c) Students could construct their own solenoid by wrapping wires around a broom handle (or

similar) and then removing the dowell and then investigate the effect on a plotting compass as

the current is switched on and off.



The strength of an electromagnet can (a) Some students believe that the electric current flows through the coil of wire and into the iron

be increased by the presence of an and that the electric current then turns the iron core into a magnet. Actually, there is an electric

iron core current in the coils of wire of the solenoid and this creates a magnetic field, magnetising the iron

core. There is no current in the iron core. Discuss this with students to ascertain their starting

point

(b) Students could construct their own electromagnet by wrapping a few turns of current

carrying wire around a long iron bar (perhaps a retort stand), noting that the far end of the iron

bar behaves like magnet. Compare the effects of using a wooden rod instead.

(c) Use internet resources to investigate the manufacture of commercial electromagnets

Knows that the strength an (a) Use a simulation package, such as Focus Science Investigations that allows students to

electromagnetcan be increased by model the magnetic effect of increasing current, in terms of the number of virtual paper clips the

greater current electromagnet can pick up.

(b) Students can perform an investiagation where an electromagnet is connected in series with

an ammeter and a variable voltage power supply. How many paper clips can the electromagnet

lift at different currents.

(c) As (b) but card or beer mats are placed between the electromagent and a paper clip. What

is the 'drop current' at different thickness of card. This investigation can be related to car

manufacture because a similar technique is use to see if the correct thickness of paint has been

applied.



8K Light

QCA sub-objective Suggested action IoP relevant slide:

Know which materials are transparent (a) Provide a range of materials that are either transparent or opaque. Ask the students to sort

or opaque into materials that it is possible to see through and those that it is not. Introduce the keywords

'transparent' and 'opaque', paying particlular attention to 'opaque' as it is an uncommon word

and label the two groups of materials.

(b) Give the students a spelling test, introducing the words 'transparent' and 'opaque' and then

ask them to produce a wordsearch containing these, and other keywords. An extension activity

is a wordsearch or crossword with clues to the keyword.

(c) Write the words 'opaque' and 'transparent' on 5 posticks each. Students to go around the

classroom correctly sticking the postiks on transparent and opaque objects and then try to

locate the postiks of other students.

Know that when an opaque object (a) Produce a puppet show 'the Opaque Players', using silhouettes of figures on sticks in a dark

blocks a path of light a shadow is room with a bright light source. Write a play where the words 'transparent', 'opague' and

formed 'shadow' have to be included.

(b) Place a large flipchart paper on a wall and illuminate a students profile. Draw around the

shadow and afterwards, cut out, mount on black paper and make a wall display. The students

are to explain what they have done using the word 'opaque' and 'shadow' and even 'silhouette',

emphasing that light has been blocked out to form the shadow and that a shadow is formed due

to the absence of light.

(c) Using a ray box without a lens to it forms a wide beam, produce shadows by putting objects

in the way. This helps students to identify that light comes from a source. Then ask students to

spot other shadows at home or around the school, and try to find the light source in each case.

(d) Compare shadows by using sources of differing intensities shining on an object from

different directions.



Know that we can see clearly through (a) Introduce the keyword 'translucent' as being a substance that lets some light through.

transparent materials but not Provide a range of materials for students to sort into transparent, translucent and opaque

transluscent groups by shining a light through them or holding up in front of a projector.

(b) Use a data-logger and light sensor to compare the amount of light that is transmitted through

different materials and tabulate their results.

(c) Pose the question 'is it possible to get a suntan when swimming?' and discuss ideas and

experiences. Imagine deep sea and describe what it is like - cold and dark because the light

doesn't get down that far really. Introduce the idea that water looks transparent but it is

translucent if deep enough and so the words 'transparent' and 'translucent' depend on the

dimensions of the medium not just the material.

Know about luminous and non- (a) Consider with the students the keyword 'luminous', what do they think it means? Introduce

luminous objects some examples of objects that give off their own light eg a lit torch, candle or match. Define

luminous objects as those that give off their own light and ask if they agree that everything is

either 'luminous' or 'non-luminous'.

(b) Use a yellow highlighter pen to colour-in all the luminous objects in a picture of a room.

(c) Students play a pairing cards game, where the names of a variety of objects are on upside-

down cards, some of the objects are luminous and some are non-luminous. The students are to

turn over two cards and remove them if they are both luminous or non luminous. If they fail to

pair up two then the cards are returned faced down and another person has a go.





Know that we see non luminous (a) Elicit students' ideas about how we see things. There are three basic misconceptions: eg

objects because they reflect light to "Light filled the room" i.e. the light is just there, "throw glances" i.e. the 'active' eye gives out

our eyes something like a spotlight, "light goes into our eye so we can see" i.e. the light goes straight into

the eye. Discuss these misconceptions drawing pictures to identify what they mean.

(b) Consider how we see objects by constructing the path from the 'source', to the 'object', and

into the eye through a 'medium'. Note that light travels to an object and then is reflected off non-

luminous obejects in all directions but some of this reflected light goes into the eye.

(c) Students should experience being totally in the dark - or at least as near as possible, use a

bright torch to light a circle and ask the students to explain how it is possible to see objects,

emphasising that that light is travelling into the eye.







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KS3

Know that shiny objects reflect more (a) Some students may believe that light is only relected off mirrors and find it difficult to

light than dull objects comprehend that dull surfaces including people, walls, rocks, wood etc., are reflecting light.

Reinforce the idea that light comes from a source or luminous object and goes into the eye,

often by bouncing off objects first. Locate objects on a scale of reflectivity from mirrors at one

end of the scale to black matte paint on the other. Students could be shown schematic

diagrams or electron micrographs of ultra smooth vs 'bumpy' surfaces to see why (smooth)

shiny things reflect light so much better and therefore seem shiny.

(b) Introduce the idea of diffuse reflection by discussing snow and skiing holidays. Often

sunglasses have to be worn because of the glare but it is not possible to see a reflection of

yourself in the snow.

(c) Survey lighting at home, listing the room, type of bulb, type of fitting, power, colour.

Importantly, ask if the lighting is direct or indirect i.e. does the light go directly to the person or

is it ambient lighting that reflects off walls and ceilings. Comment on the wall colour and the

light level in the room, comparing the

reflectivity of gloss and matte paint.

Know (qualitatively) how light is (a) Introduce reflection using a torch in a darkened room. Ask the students to predict where the

reflected at plane surfaces and reflected light rays go. Emphasise that light comes from the source and is reflected from the

describe reflected images objects in the room, some of this reflected light will enter the eye and some will scatter off the

objects elsewhere in the room. Some of this scattered light will enter the eye eventually as it

reflects off the walls etc, giving the impression that the whole room is dimly lit to some extent.

Draw a ray diagram of a several parallel rays incident on rough a surface, showing the reflected

rays bouncing off at random directions.

(b) Draw several parallel light rays incident on a plane mirror. Note that they all reflect off so

that they still remain parallel and compare with scattered light.

(c) Arrange two mirrors so that it is possible to see the back of your head. Students are to draw

the ray diagram from the back of the head to the eye. Ask where the source of the light is and

ask them to put this ray onto the diagram.

Know that an image formed in a (a) Introduce the idea of the nature of a mirror image produced in a plane mirror. Ask students

plane mirror is laterally inverted how such an image differs from the object viewed, and explore their explanations of why this

happens. Students in pairs, to role play a person in a mirror, where one person pretends to be

the mirror image of the other.

(b) Ask students to explore the symmetry of images by predicting and testing which capital

letters or words are symmetrical and by attempting to write words in 'mirror writing'.

(c) Students could compare a photo of their reflection in a mirror with a photo taken front-on - in

photos we look the wrong way round because we're used to seeing the inverted reflection in the

mirror



Understand that light travels in (a) Show the students a sequence of photographs of beams of light eg light shining through

straight lines clouds, light rays in a mist, and spotlight beams where straight lines are clearly visible. (b)

Show pictures of sharp shadows eg skiing pictures or sundials. In a dark room cast a shadow

onto a screen using a bright light source, encouraging students to explain the phenomena in

terms of a sequence beginning with light leaving a source, travelling through a medium and

hitting the object. Students to draw a diagram explaining shadows - a ruler is essential, and to

be clear that the shadow is formed when light is blocked. (c) Use a laser in a dark room to

produce a spot on the wall. Then, sprinkle talc or chalk dust in the path of the laser beam and a

straight line can be seen. Discuss why the dust enables us to see the beam. Emphasising that

the only reason is that light is scattering off the dust into the eye.



Know how to represent the path of (a) The first point to make clear to students is that a ray diagram is a simplication of a real

light by rays event in order to only study information that is relevant. Also a light ray is a theoretical

construction rather than something real (we should not refer to rays of light travelling away from

a lamp) and that there are countless possible rays that could be chosed and it is our task to pick

the key ones that are most useful to what we are trying to say. By making these points clear to

students they should use ray diagrams to explain and predict events rather than go through the

motions because the teacher tells them to.

(b) Show how a specific ray diagram is constructed making clear to the students all the thinking

behind the various stages. Use the examples of constructing a ray diagram for a shadow and

for a pin hole camera image. Make sure that the diagrams are drawn in pencil, all rays are

drawn with a ruler, and all rays carry an arrow showing the dirction of light travel.





Know how to identify the correct (a) Roll a small ball on the floor so it hits the wall and bounces off at about 45 degrees. Repeat

reflected ray from a plane mirror this for a number of different angles, without comment, and ask the students what they notice

about how the ball bounces away and then to predict the direction that the ball will bounce off

at. Consider what is meant by the term 'angle' and to predict the angle of relection of the ball

Make the point that the aim of the activity is to think about light reflecting not bouncing balls.

(b) Locate a projector in the middle of a room so that it casts a narrow beam of light across the

lab. Switch off the lights and locate the beam. Ask students to predict where a mirror will reflect

the beam to on the wall and then try out. Repeat with different mirror angles, establishing the

idea that the more the angle is turned the greater the angle of relection.

(c) Students working in pairs with ray boxes establish the idea that the 'angle going in is the

same as the angle coming out' by using relection of the ray in plane mirrors and measuring with

a protractor. Measure the angle from the mirror to the rays before and after the reflection.





Know how to apply understanding of (a) Introduce the keyterms: 'incident ray' as the ray before reflection,'reflected ray' as the angle

angles of incidence and reflection after reflection, 'the normal' as a theoretical line perpendicular to the mirror, 'angle of incidence'

as the angle between the normal and incident ray, and 'angle of reflection' as the angle between

the normal and the reflected ray. Concentrate on discriminating between these angles and

those between the mirror and the rays.

(b) Demonstrate the correct ray diagram construction of a reflection in a plane mirror on an

OHP, but pause before drawing the reflected ray. Ask the students to predict the angle at which

it should be drawn, refering to any earlier work with bouncing ball etc. Elicit from them that "the

angle of reflection must be equal to the angle of incidence" and test using a ray box on the OHP

that the theory is correct.

(c) Students to work in pairs using ray boxes with slits to check if their predicted ray diagrams

are correct.









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Know about applications of reflection (a) On a piece of plain paper, students to draw the predicted reflected ray of two plane mirrors,

two mirrors and then test out their predictions using a ray box and slit.

(b) Tell the students that they are going to use their knowledge of the law of reflection to invent

their own device that uses muliple mirrors eg a device for looking over high walls around

football grounds. Ask them to make a careful drawing of the invention, showing each of the

mirrors, and to draw a single ray of light to show how it passes around the mirrors and into the

eye. At each of the mirrors be sure to include the normal line and mark the angles of incidence

and reflection.

(c) Using a prepared worksheet showing the cross section of a periscope, students to show the

path of light. Test them to see if they put the arrows on correctly and use the angle of relection

correctly.

Know the effect of a prism on white (a) A shallow cookery dish, filled with water, and placed on an OHP, usually casts a 'rainbow'

light on the wall. Examine the colours - how many are there and in what order are they in? Relate to

a rainbow.

(b) Demonstrate a of a beam of white light incident on a traingular prism in a darkened room.

Make a poster, carefully drawing the colours and develop a mnemononic for remembering the

order of the colours of the visible spectrum eg Richard Of York Gave Battle In Vain.

(c) Research the work of Issac Newton on Light, especially on his attempts to further split the

colours of light. This last point is important because white light is made up of the superposition

of fundamental colours.



Know about simple refraction effects (a) Some students only associate refraction with something that occurs with rectangular glass

blocks. Research other refraction effects such a diamonds twinkling, mirages in the desert and

'bent pencils' in water. An interesting demonstration is to make a test tube invisible by putting it

in a beaker of glycerol - here the light travels the same in both media and the glass boundaries

cannot be seen.

(b) Demonstrate careful ray diagram construction of refraction on a OHP or using a PowerPoint

presentation. Discuss student experiences of swimming pools appearing to be shallower than

they actually are, and construct a ray diagram to explain why a fish appears to be swimming at

a shallower depth.

(c) Set up the 'reappearing coin in a cup of water' demonstration and ask pupils to explain how

it works. Here a coin is placed in a cup and the eye is lowered until it is just hidden by the ridge

of the cup. As water is poured in the coin can be seen again!

Know that the dispersal of white light (a) Research information about know speeds of light in different mediums. Tell students that if

to give a range of different colours is you look at the 'small print' the speeds are for light of one colour. Ask reasons why the small

a form of refraction print is there - the answer is that different colours travel at slightly different speeds in different

media. The values most often stated are for the speeds of yellow light. (b) Confirm that students

are aware that white light is the overlapping of the seven visible colours. When white light hits

another medium, the colours disperse because the seven visible colours travel at different

speeds in the new medium. Demonstrate this by performing refraction experiments with glass

bocks and a ray of coloured light. Different colours should be bent by varying amounts given the

same angle of incidence. (c) There are several challenging questions that students could

research and present their findings to the rest. The challenging questions include: Why is the

sky blue?, Why are fog-lights monochromatic? Why do diamonds twinkle?.



Know about changes in the path of (a) Provide students with a range of glass or perspex blocks of different shapes, including

light when refraction occurs . retangluar and semicircular, and ask students to investigate their effects on a single ray of light

produced by a ray box. Ask them to look for patterns in their observations and to note light rays

bend towards the normal in the glass.

(b) In contructing a ray diagram for refraction, firstly a normal is drawn perpendicular to the

boundary at the point where the incident ray hits the boundary, i.e. four quadrants are made.

Make it clear to the students that any refracted ray must emergy in the opposite quadrant.

(c) There is an analogy with go-karts rolling down grassy hills that helps to explain refraction.

Running along the bottom of the grassy hill is a tarmac road - surely the go-kart will be crushed

by traffic!! Only refraction can save it now. If the go-kart hits the tarmac at an angle, one of the

wheels momentarily moves faster than the other which is still on the grass, consequently the go-

kart alters course. Emphasise that if a light beam enters a medium where it travels faster, it will

bend away from the normal.



Know what effect colour filters have (a) Ask students to explore how coloured filters affect light by producing a spectrum and

on white light allowing this to pass through filters of different colours.

(b) students investigate passing white light through one filter and then through a second filter.

(c) Discuss how 'black' can be formed. Introduce the key concept that black is the absence of

colour. Materials can look to have a black colour if all the colours of light are absorbed by it and

none of them are reflected.



Know that coloured filters absorb (a) Some students believe that a filter gives colour to white light rather than removing the other

some colours and transmit others colours of the spectrum. Students use data-loggers and light-level meters to investigate the

intensity of light as it passes through a filter. The intensity should drop indicating that some the

light has been removed by the filter.

(b) Produce a poster where the seven visible colours are incident on a filter as distinct bands of

colour of equal thickness. The transmitted colour is only a seventh of the total width, indicating

that other colours have not made it through the filter.

(c) Discuss the effect of placing two differnt coloured filters behind one another. The results

should be black as the result of no light passing through.

Know that we see objects as coloured (a) Inform students that when light hits an object three things can happen: light is either

because they absorb some of the transmitted through, reflected back or absorbed by the object (making it hotter). Demonstrate

colours of white light and reflect refelection and transmission by making a white light ray incident on a glass block - some is

others refracted (transmitted) but there is also a weak reflected ray. Now, remind students that white

light is made up of a spectrum of colour and that propose the theory that in most objects the

different colours are transmitted, absorbed or reflected. Discuss how this theory may make

objects look in normal light.

(b) Ask the students what is meant by the term 'white light'. Inform the students that white light

is an expression for normal light.

(c) Produce posters explaining how light interacts with objects and why objects are seen as

different colours. The thickness of the transmitted, absorbed and reflected rays varies

depending on the material and colour of the incident ray but always the total width of the three

resultant phenomena is equal to the thickness of the incident ray.









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Know how primary colours can be (a) Put a drop of water on a television set and observe closely. The individual primary colours

combined to form secondary colours should be seen. Alternatively on an old tv or colour monitor, a powerful magnet near the sreen

distorts the colours and bands of green, blue and red light can clearly be seen.

(b) Many students will have experienced mixing of primary colours together in art lessons and

will be confused that light does not behave in a similar way. especially mixing more pigments

together makes a darker colour. Emphasise that with light, this is not the case and actually

added more light of any colour will make light more intense. Students to produce wall displays

comparing colours in science and art.

(c) Coloured light sources can be superimposed in a darkened room and the results recorded.

Alternatively, software images showing mixing of colours of light are common and could be

projected up so that students can see for themselves the mixing of light



Know the effect of different coloured (a) 'Colour' is considered by most people as an inate property of obects: "Light just lets you see

light on coloured objects the colour". Look at different colour objects in different colour light by using coloured filters on a

bright projector in a darkened room. Tabulate results and discuss possible conclusions

(b) Make a brightly coloured garden gnomes trousers disappear by rigging up different colour

lights. The trousers will only be visible when light of the same colour is incident.

(c) Research 'green-tinting' which is a way that television studios using a green background and

superimpose weather maps when that colour is removed from the recieving spectrum.







8L Sound & hearing

QCA sub-objective Suggested action SPT relevent slide:

Know that sounds are created by (a) Show examples where vibrations are easily seen eg tuning fork and polystyrene ball,

vibrations loudspeaker and grains of sand. (b) Provide familiar sound sources or pictures, eg musical

instruments, and ask students to identify which parts vibrate to make the sound. (c) Students to

make a musical instrument by folding tissue paper over a comb and blowing through the paper.

The instrument make a noise and students can fell vibrations on their top lip.



Know a range of sources of (a) "If you hit a cymbal it vibrates to make a sound. If you drop a spoon on the kitchen table it

sound/vibrations just makes a noise". Students need to know all sounds are produced by vibrations. Where the

vibration is less obvious, they tend to revert to ad-hoc explanations for the generation of sound,

often focussing on human action eg ' the stones are making that noise because you are rubbing

them'. With the students identify what could be vibrating for every sound they hear. A

microphone connected to an oscilloscope with the time base off, will be deflected up and down

for all sounds and noises. (b) Students could twang a ruler that is overhanging a table and held

tightly at the other end against the table. By adjusting the length of the overhang different

pitches can be heard. Students to describe in their own words the experience. (c) Students to

research how humans can sing, including the function of vocal chords and the air boxes of the

lungs and nasel cavities e.g http://www.voiceproblem.org



Know how notes of a different (a) Demonstrate how a musical instrument can make notes. Identify that there are distinctly two

loudness are produced in musical different qualities - pitch and loudness. Elicit that louder sounds are make by blowing or

instruments, eg the bigger the plucking harder whereas pitch is caused by faster vibrations. (b) Demonstrate a Rolf Harris

vibration the louder the sound 'wobbleboard' using a sheet of thin plywood or such like. Note that louder sounds can be made

if the 'wobbleboard' has large amplitudes and also that more energy has to be put in to make

the loud sound. Confront the student misconception: "With bigger vibrations it will sound higher"

by eliciting that the sound produced is the same pitch and that louder sounds are formed with

bigger vibrations. (c) Connect a signal generator to a large speaker. Make it clear that the

frequency control is not being altered but loudness can be be adjusted by only altering the

volume control. Close inspection of the paper cone of the speaker should show that quiet sound

have low amplitudes.



Know how notes of a different pitch (a) Students can make a musical straw by flattening the end of the straw and cutting off corners

are produced in musical instruments so that it makes a rudimentary reed. By blowing into the straw the newly made flaps vibrate and

the straw makes a 'kazzoo' sound. By cutting the straw whilst it is being blown into shorter

lengths the pitch can be distinclty heard to increase. (b) Demonstrate two Rolf Harris

'wobbleboards', one large and one small. The two boards give off a different pitch note no

matter how hard they are vibrated. (c) Connect a signal generator to a large speaker. Make it

clear that volume is not altered by when the frequency dial is altered the sound changes pitch.

Students can gently touch the paper cone through a range of frequencies. Introduce the term

'frequency' and ask what the students think it means, concluding that it is the rate that the

speaker vibrates and that the pitch of the sound is related to frequency..



Understand that sound travels as (a) There is a student misconception that "Sounds come down the cable". Sound is not 'stored'

vibrations which push particles to on a CD, sound only comes after the loudspeakers and students have to identify 'sound' as a

make a wave particluar type of energy transfer. Follow the path how live music gets from a studio to a living

room, through sound wave to electrical signal to radio wave back to electrical signal and to

sound wave again. (b) Imagine the largest 'jelly cube' in the world. Imagine putting your ear to

one side and somebody else kicking the opposite side. Pose the question "would it be possible

to 'hear' the kicks through the jelly" and discuss student perceptions. Show a Newton's cradle

and ask what relevance has this to hearing sound - the idea is to show that particles can

transfer energy to each other. (c) The BBC 'Class Clips' KS3 DVD has some excellent short

clips and animations that will help students to visualise sound waves.



Know how changes in pitch and (a) There are two big dangers of using an oscilloscope - sound is a longitudinal wave rather

loudness of sound relate to changes than a transverse wave and second, it is tempting to point to the wave on a screen and identify

in traces on an oscilloscope a wavelength as distance between crests. Actually the horizontal axis is time. It is important to

explain to students that what they are seeing is actually a picture or representation of sound and

that it may be benificial to start with the time base set to zero so the point vibrates about the

same spot. (b) Connect up a microphone to an oscilloscope and whistle into the microphone.

Can the students notice the difference in the signal? Alter the time base so that the frequency

variations can be seen. Draw different frquencies for the same time base and relate to the pitch

that can be heard. (c) Look at the insides of a microphone. Identify a vibrating membrane that

sends out an electrical signal to the oscilloscope.









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Know how traces on an oscilloscope (a) Connect up a microphone to a oscilloscope and also a signal generator to a large speaker.

relate to amplitude Ask the students to describe in their own words what would be seen on the screen if the

frequency dial constant is kept constant but the volume is changed. Test out predictions. (b)

Identify 'amplitude' as a keyword and relate to loudness. (c) Provide representations of different

sound waves and ask pupils to indentify, eg the loudest, lowest. Relate to sea waves crashing

on a beach - big waves mean loud waves, but lots of quick waves means high frequency (or

pitch).

Know that sound cannot travel in a (a) There is a student misconception, summarised by: "I had turned my radio on very loud and

vacuum music just filled the house". Here, the problem is could be that they don’t appreciate that sound

travels through a medium rather than an entity that flows into a room. Cosisently stress the

need for a source-medium-detector model when considering different sounds. (b) Many

students do not really have a conception of what a vacuum is, even Space requires quite an

imagination. Discuss with students what is between air partcles and what is left in a gas jar

when the air is pumped out. (c) Show conflicting TV footage (spaceships, superman etc) where

explosions are clearly heard as well as seen. Ask what is wrong with the footage and what

should 'sound' sound like in Space. This is of course, a trick question, as sound cannot be

heard in Space.

Know how sound travels much (a) There are two levels here: appreciating that light is faster than sound and that light is

slower than light x1000000 faster than sound in air. The second level is an important step as students begin to

appreciate scale. Even the first level is not an everyday experience for most people because

most things seem to make a sound straight away. Discuss student experiences of seeing

fireworks and jet planes before they hear them. (b) Experience echoes by taking students to a

large wall and clapping wooden blocks together. Ask the students why echoes can be heard

and then why a time delay is never noticed if you look in a mirror or shop window. (c) Use the

internet or other resource to find the values of the speed of light and the speed of sound in air.

Ask the students to calculate how many more times light is fater than sound.



Know that sound travels at different (a) It is important to realise that young students would never have experienced or noticed sound

speeds in different types of material travelling at different speeds through different materials. Firstly establish that sound can travel

through solids and liquids by asking questions such as "Can you hear through closed doors?

Can animals hear underwater?" and demonstrate that it can by listening to sound through a

wooden bench or by making a string telephone. (b) Consider the theoretical model of particles

and how they transmit sound. Show a Newton's cradle and discuss what would be the effect if

the balls were further apart so they can to swing a bit before they hit a neighbour. Conclude that

if the particles are close together, like in a solid, sound will travel faster. (c) Research the speed

of sound in different material and present on a class bar chart.



Know about energy transfer involving (a) There is a student misconception that "Sounds run out as they get further away from the

sound source, and eventually stop". Sounds "die away". The answer is that the energy of the particles

is more spread out as there are more and more particles involved -like ripples spreading out on

a pond. Discuss the analogy of circular ripples on a pond and how it compares to sound,

emphasing that sound propagation is in 3D. (b) Using a sonic ruler to measure distances

around the room and then draw an accurate floor plan. (c) Show images of unborn babies using

ultrasound and students to research the reasons for a gel between mother and reciever; and the

limitations of using ultrasound eg it cant be used for images of lungs.



Understand how particle theory can (a) There is a student misconception that "The air just in front of loudspeaker is pushed into

explain how sound travels through your ears" Sound is not a packet that travels from source to ear. A good counter argument is

materials that sound travels through solids.Students to put their ear on a table and listen to sounds

coming though the table. This may help the students appreciate that sound is getting to them

through wobbles in the table. (b) Students to draw a poster, showing how sound travels through

a medium from a source to a detector. Encourage students to show sound spreading out from a

source and not just a single straight line. Ask students why sounds are quieter further from the

source. (c) Use hand held sound meters to investigate 'sound shadows' ie. areas behind

obstacles where the volume of sound should be less. Research why sound shadows are less

definate than those of light.

Know why sound travels faster (a) The key here is to explain that if the particles are closer, they knock into each other quicker.

through solids and liquids, using The particles have shorter distance to travel and so hit a neighbour more quickly. Role play

particle theory and understanding of sound propagation at arranging students so they stand half a meter apart. One student starts

energy transfer rocking gently back and forth, from one foot the the other. As he/she touches their neighbour

they start rocking and so on until the 'sound' moves down the line. Now position them closer so

that they are almost shoulder to shoulder. This time the sound should propagate down the line

quicker. Discuss the relevence of sound travelling in solids, liquids and gases (b) Students to

listen closely with an ear to a metal railing that is tapped some meters away. Inform the

students that sound travels five times faster in metal than in air and ask them to pictorially

explain why.

Know that the effects of vibration to (a) Elicit ideas from students about how we hear sounds. A model eardrum, eg balloon material

the eardrum are transferred to the stretched over a large beaker, can be used to demonstrate the how vibrations can lead of

brain Know that sound makes the changes of air pressure in the ear (beaker). Discuss experiences of ears 'popping' (e.g. at

eardrum vibrate and this is how we height, on a plane, under water) and relate hearing to air pressure changes. (b) Describe the

hear scenario of shouting to somebody on a really windy day and ask the students to explain why

they cannot hear you. (c) Demonstrate a large speaker showing the paper cone moving up and

down in response to electrical signals. Tell the students that the ear works like this in reverse -

like a microhone. Ask the students to write in their own words the energy energy transfers

associated with an ear.

Know that animals & humans have (a) Use an audio signal generator to generate a range of sounds of different pitch. Clearly

different hearing ranges (including demonstrate that the volume control has not been altered. Ask the students to all raise a hand

different hearing ranges in humans) and lower it again when they can no longer hear the sound. Establish an upper and lower range

and discuss why a teacher often can't hear the same range as young people. (b) Software such

as Multimedia Sound can provide a spectral analysis of sound. Here, the whole range of

superimposed frequencies from a sound are shown graphically. Inform students that there is a

window of sound which it is possible to hear and that many sounds go unnoticed by the

eardrum. (c) Discuss with students what they know about the hearing range of animals eg long-

distance communication in whales, ultrasonic echo location in bats, and dog whistles.

Demonstrate the use of a dog whistle









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KS3

Know how the ear works (including (a) Show them an anatomical model of the ear, illustrating the relative sizes of the parts and

describe translation of sound waves how they are connected. Explain how the eardrum vibrates as a result of sound entering the

into electrical signals which are ear, and the transmission of vibrations to the inner ear. In the inner ear, vibration is changed

transmitted to the brain) into electrical signals that are sent to the brain via the auditory nerve. (b) Students to produce a

leaflet "How we hear", intended to be shown to parents at an open evening. (c) Students to

investigate whether two ears are bettter than one in detecting direction of sound by blindfolding

a volunteer and asking to point to the source of sound, then repeating but with an ear plug in

one ear.

Know ways in which hearing can be (a) The BBC's Class Clips DVD shows footage of the function of auditory cells and because

impaired they die off, people's hearing range naturally deteriorates with age. Contrast sound to light, in

terms that it is possible to determine with sound individual frequencies whereas with light a

superposition of frequencies leads to a new colour. Consequently, the range of sound that

people can hear can change with age, whereas the range of colours people see generally does

not. Students to explain why music could actually sound different to older people. (b) Students

to research the ways hearing can be impaired interms of loss of auditory cells, hardening of

eardrum, or problems with ear bones. They could present their work to other students using

OHP and flipcharts to other students. Encourage students to compare their own presentations

with those of others and to identify good and bad points in them. (c) Research Hearing Aids and

how they have become more advanced but still do not fully replicate a healthy ear. Investigate

hearing cones made out of rolled up paper and whether or not they do improve hearing.



Know how to relate hearing (a) Present students with information about hearing impairment, eg among different age groups,

impairment to possible causes and ask them to suggest possible reasons, eg exposure to loud sounds at work, exposure to

loud sounds when young, inherted deafness. Help students evaluate possible explanations and

to think of reasons for supporting and rejecting them. (b) Use some accounts of people's

experience of temporary deafness or tinnitus to discuss with students what excessively loud

sound can do to hearing. Use a model or diagram of the ear to discuss what might cause the

problems.

recalls that the loudness of sound is (a) Introduce Alexander Graham Bell, who is credited with inventing the telephone, and that the

measured in decibels measure of loudness is named after him - the bel, and that one tenth of a bel is a decibel. It is a

complicated scale, a bit like the Richter Scale that measures scale earthquake magnitude, but it

ranges from 0 dB, which is the threshold of human hearing to 140 dB, which is a billion times

greater. (b) Students to research decibel values of aircraft noise, rock concerts etc., draw a

picture of the source and plot on a large scale for all to see. (c) Use portable dataloggers to

measure decibel values around the school.

Know that loud sounds can damage (a) Raise issues of noise pollution eg near airports, due to traffic and listening to loud music.

the hearing Relate to a model or diagram of the ear and ask how either excessively loud events or

prolonged exposure can possible damage parts of the ear. Discuss any experiences of ear

damage due to noise pollution. (b) Research current law regarding workers rights to noise

pollution and present to other students. Use sound-level meters to compare the levels that they

are exposed to during the course of a day. (c) Use a sound-meter to measure the rate at which

sound diminishes from a source and graph the results.



Know ways in which to reduce noise (a) Investigate the effectiveness of spongy materials and rough surfaces as sound insulation, eg

pollution with a clock in a box filled with different absorbent materials. (b) Research anechoic chambers

used in, for example, concert halls, recording students and even car research plants. These are

chambers where ambient noise is reduced to a minimum so that only sound eminating directly

from the source is recorded, as opposed to also recording echoes off walls. The chambers are

characterised by very irregular walls made of spongy material - ask the students to explain way.

(c) Consider ways in which people who exposed to loud noise as part of their daily work are

protected from noise pollution (ear phones, ear plugs, exposure restrictions) and how hearing

capablility can be tested.



Unit 9I Energy and electricity

Sub-objective Suggested action SPT relevent slide:

Know that energy is converted from (a) Energy is not a physical quantity that makes things happen, it is an abstract quantity that can

one form to another to be useful be calculated in many ways. Relate Energy to an amount of cash - the quantity that you have

limits what you can do but does not compel you to do anything. Introduce the currency of energy

to be a Joule, rather than a £ or $. (b) 'My auntie used to keep money in different pots around

her house and sometimes take money from one pot and put it in another', in a similar way

energy is stored in different ways and shifted from place to place. Recall some of the names of

the various 'energy pots', eliciting answers such as 'kinetic', 'heat', 'potential', 'sound' . Draw a

picture of an auntie moving energy around her house from one pot to another.



Know that energy transfers and (a) It is often not useful to think of types of energy but it is better to think of energy being the

transformations are involved in useful same, wherever it turns up. However, energy shifts from one store to another. Provide the

energy changes students with cards with 'types' of energy store labelled on them, which are consistent with their

experience of energy teaching in previous years eg 'gravity', 'elastic', 'thermal', 'sound', 'kinetic'

and 'chemical'. (b) Explore an energy circus with a range of toys and devices, asking the

students to pick the energy store before and after. (b) Things get done when energy changes

from one store to another but it is important to point out that sometimes things 'get done' without

there being any shift in energy. Consider various situations where things are happening, such

as: car driving along a road, rockets taking off, a cannonball falling back to earth, spacemen

drifting through space, the Moon orbiting the Earth, an object on a spinning planet - and ask

which of this situations involve energy change (the first three) and which do not (the last three).



Classify devices on the basis of type (a) Ask students to explore a circus of toys and devices, eg battery operated vehicles,

of energy input or output clockwork toys, electric bell and a yo-yo. In each case they are to identify the source of energy

and the principle output. Group the devices together in terms of a common input or output and

add some other examples not seen. (b) Provide the students with cards with 'types' of energy

store labelled on them, which are consistent with their experience of energy teaching in

previous years eg 'gravity', 'elastic', 'thermal', 'sound', 'kinetic' and 'chemical'. Show the students

devices that convert energy from one source to another eg a steam engine and ask the students

to place cards on either side of the device to show input and output energy. (c) It is difficult to

label 'electricity' as an energy source because it really is a method of transferring from energy

stores. Consider the generation of electricity using a generator or dynamo and identify that the

original store of energy is chemical.









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Know the advantages of using (a) Electricity is not a thing but a means of transferring energy from one store to another.

electricity as a way to transfer energy Consider the big picture that electricity has made it possible to tap into the stored energy in

coal, oil and wind, so that the energy can be brought to our homes. Think about lifestyles before

electricity eg gas-lamps, only live music etc. Ask the students to sum up the impact that

electricity has had on lifestyles in a few concise sentences. Elicit ideas that life would be dirtier,

less-convenient and that there would be far less communication around the world. Electricty has

changed everybody on the planet, forever. (b) Brainstorm with the students devices around their

home that 'use electricity' and ask them if they had to choose, which one would they get rid of.

Discuss that we are as a society, dependent on electricity and think about the future. What new

inventions are their going to be? What is the world going to be like in 50 years? When batteries

and solar panels get more advance, what kind of clothing will we have?

http://youtube.com/watch?v=Yd99gyE4jCk .

Know about energy transfers in (a) Identify the energy in certain foods from the packaging and calculate the energy consumed

everyday changes by a student in a day. Consider where that energy has gone and the effects on the body of

eating too much or too little. Emphasise that a person's body requires a certain amount of

energy to keep warm and functioning. (b) Compare a standard light bulb with an energy efficient

one. Ask the students to touch the bulbs - careful, the standard one is hot! Consider the energy

going in and coming out of the bulbs. Do we want light bulbs to get hot? Why does the energy

efficient light bulb use less electricity in the same time? Elicit from students ideas that many

devices transfer energy to forms that are not useful



Recognise ways in which energy is (a) Define 'fuels' as chemicals that can be burnt to get things done. Brainstorm types of different

stored fuels including food. Fuel is a physical thing associated with an energy store but ask if other

situations can be associated with a storing energy. Elicit ideas about objects held high up have

an energy store, as do springs under compression, hot objects, and even moving objects have

a store of energy. (b) Students need to develop the idea energy stores often depend on more

than one object eg fuel-plus-oxygen and object-plus-Earth are the energy stores.



Understand that transducers can give (a) Indroduce the term 'transducer' as any device that gives out energy and challenge the

out energy when put in an electrical students to name ten transducers in 30 seconds eg light bulb, TV, cooker. Inform the students

circuit that a more limited definition is that a 'transducer' conversts a signal to one form to another and

includes gramophone pick-up's, piezoelectric crystals and Geiger-Muller tubes (make a clicking

noise when radiation present). Ask the students to name some transducers using this narrower

definition, but only to help them clarify their thinking to electrical circuits. (b) Energy boards

such as those from the Science Enhancement Programme

(http://www.mutr.co.uk/prodDetail.aspx?prodID=394) are a useful resource to show various

types of transducers on a board. For each devices, students to name the type of energy outputs

(c) Discourage any ideas that electricity is a thing at moves from point A to B. Instead

encourage a model that electricity is more like a bicycle chain transferring energy from one

store to another.

Know that an ammeter measures (a) Study the work of Ampere to give a context that the ammeter is named after a famous

current scientist. (b) Introduce different types of ammeter that students may come across in science

including an digital and analogue meter and recall that it is used to measure electric current.

Emphasise that all ammeters have got a postive and negative terminal. Ask the students to

imagine that there is a 'little helper' inside each ammeter with a counting stick in one hand and

a watch in the other. The helper counts the number of electric charges that pass in front every

second and displays the value on a screen. So how should we connect the ammeter so the

helper can do its job? Elicit ideas that the ammeter has to be part of the circuit - put in as you

would put in a new piece of track on a model railway. (c) Challenge students to correctly insert

ammeters into circuits. Use simple circuits with one or two bulbs and ask them to measure

current at various points in the circuit.



Understand how current behaves in a (a) Demonstrate using a rope loop to represent current. Here, the rope is pulled around by the

simple circuit teacher and is held by a student. If the student holds tighter than it is harder for the teacher to

pull the rope i.e. there is more resistance. Introduce the idea that the current is the amount of

rope that passes a point each second. Discuss the speed of rope at various points in the circuit -

it is the same! In the same way current is the same at all points in a simple circuit. (b) Ask the

students to measure the current using an ammeter at apoint in a simple circuit. Challenge

students to predict the currents at various other points eg after the bulb or between two bulbs,

and then to check out their predictions. As many students are not yet certain of the significance

of decimal points, it is advisable, to use ammeters that are not too sensitive. Digital ammeters

that measure to 2 dp may give readings of, say, 0.48V and 0.49V. There is no relevant

significance in the difference but can confuse students.



know that a voltmeter measures (a) Show the students various types of voltmeter (analogue, digital), emphasising that they

voltage come in different shapes and sizes but all have two terminals and all measure in 'volts'. Draw

comparisons with how ammeters look, pointing out any differences such as location of terminals

or coloured shunts. (b) Imagine two corridors of students moving from one class to another. It is

possible to say that one corridor is much busier compared to the other. In the same way, a

voltmeter compares the energy between two points in a circuit. One terminal is connected to

one place and the other is connected to another place and the difference in the energy between

the two places comes up on the screen. It may be useful to introduce an alternative term for

voltage as 'potental difference'.



Understand the link between energy (a) Model 1: A rope loop is pulled by a teacher through the fingers of a student. The students

and voltage using a simple model fingers get hot because of the work done by the teacher. If a second student is added to the

circuit, the teacher has to work harder to heat up bothe their hands. The energy in is now

spread out over two people. A voltmeter could measure the amount of energy transferred

across each person in the circuit (b) Model 2: The battery in a circuit relates to a ski lift. The

bigger the voltage of the battery the higher the ski lift. As charges 'ski' back down to the bottom,

they lose gravitational potential energy. When they have descended half way they have half the

original stored energy ie half voltage. (c) Model 3: A fleet of bakery vans continually drop off

loaves of bread at a supermarket. The voltage is the voltage corresponds to the number of

loaves dropped off. If there is a second supermarket and the bakery cannot increase

production, then each gets some of the loaves and so the voltage across each drops.









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Understnd how energy is transformed (a) The term 'cell' is often introduced without explaination. Enquire of the students whether they

between a cell and a circuit have heard of a 'battery of solidiers'. In the same way, what is commonly called a 'battery' is a

collection of electrical 'cells' working together. The cells are more obvious in a car battery. (b)

Show some pictures of simple series circuits and identify the cell (or battery) as the engine in

the circuit. Demonstrate pulling a rope loop through the fingers of students. The engine is

pulling the rope and the student is feeling the effects because their fingers are getting hot. In the

same way a battery pulls a current around a circuit and the effects are shown in the

components eg light bulbs. Another useful analogy is to use a steam engine turning a fan belt

that operates say, a loom or printing press. The engine's energy it transferred elsewhere

because of the fan belt, just as the cell's energy is transferred elsewhere because of the

current.

Understand that cells can produce (a) Research the conflict between Luigi Galvani and Alessandro Volta, leading to the first

diferent voltages depending on the battery in 1800. Modern cells consist of two electrodes of differing metals in an ionic solution.

reactivity of the metals used as The solution is more obvious in a wet cells such as a car battery, but dry cells contain an 'ionic'

electrodes paste. Draw a picture of a rudimentary cell labelling the component parts. (b) Experiment with a

simple electrical cell made with a lemon. To prepare the lemon, gently squeeze it to soften it

up, and the insert clean pieces of copper and zinc (5mm X 40mm) into the fruit, close together

but not touching. After a few minutes a votlatge can be measured with a sensitive

galvanometer. Recall from chemistry, that metals can be placed in a reactivity series and ask

the students to predict and investigate different combinations of metal. Lemon cells can also be

connected in series with each other to make a battery that can light an LED.



know that some devices use more (a) Devices convert different amounts of energy in the same time. Emphasise this by discussing

energy than others. microwave ovens that have two power settings. The directions on a microwave food packet

provide cooking times at different settings (eg 4.5 mins at 650W, 3.5 mins at 750W). Use sets

of figures such as these to help students grasp the idea that high power electrical devices can

transfer a lot of energy in a shorter period of time. (b) Relate to battery powered toys and

devices that students have at home. In their experience, which ones use the batteries up

quickest? Elicit ideas that moving toys go through batteries quickly, whereas a radio seems to

last for ages without changing the batteries. (c) Students could collect some information from

older neighbours and relatives about the appliances that they had in their homes some 30-40

years ago. Use this information to highlight how many more appliances are now more common,

and that although modern machines are less wasteful of electricity, there is a lot more strain on

resources.

know which appliances use more (a) It is a very useful exercise for students to investigate the power outputs of electrical

energy than others appliances in and around the home. By collecting the figures and grouping them according to

size, students can find out that appliances with the biggest power outputs are those that have

some kind of heating function. (b) Encourage the students to locate and look at their electricity

meter at home. If possible, the students could relate how quickly the dial goes around when an

electric cooker or heater is turned on. Compare with normal rate when the heavy heating

appliances are not on. Does turning the TV on make much difference to the speed of the dial?



Understand that some appliances (a) Ask the students, working in groups, to identify as many expressions as they can that use

transfer more energy than others in a the term 'power'. Isolate the term as having a particular and distinct meaning in science ie how

given time. much energy is transferred each second. Many students will have already come across the unit

of power, the watt, outside school. This may be buying light bulbs, choosing hi-fi systems or

adjusting the microwave. Consider experiences of using a 40W instead of 100W and use other

links to demestic appliances that help students to undersatand that power is related to energy in

a given time. (b) Introduce the term 'kilowatt hour' and ask the students to infer what it

measures. It actually is a direct measure of energy used (1 kWh = 3600000 Joules) and it is the

amount of energy used if a kiloWatt fire is on for 1 hour.. Sometimes is is called 'a unit'. Relate

to an electric bill - how much is charged for each kWh? What could be done to reduce the

electricity bill?

Understand how electicity is (a) Brainstorm the students' initial ideas of sources of energy. Elicit sources such as nuclear,

generated from a range of energy coal,oil,gas , wind, water, waves and the sun, distinguishing between sources and devices that

resources. drive electrical current, such as generators, wind turbines and solar panels. List the sources and

ask for each how electricity is obtained from them. Link the source to a device ie nuclear,

coal,oil,gas, wind, wave to a generator and the sun to photo-electric panels. (b) Look at a

diagram showing how a power station works eg http://www.uic.com.au/uran.htm. Emphasise

that the energy store is released to heat water to turn turbines to drive a generator. Ask

students what other fuels could be used to heat the water..etc. Elicit any ideas about burning

rubbish, getting methane from cows, etc. (c) Discuss the student experiences of photo-electric

solar panels. Have they seen them on houses or calculators or spaceships? Imagine all the

possibilities of improved panels. Emphasise that solar panels do not need a generator to make

electricity but do need to charge up batteries if they are to be used at night.



Know the structure of a simple (a) The key feature of almost every electrical generator is circular motion. Demonstrate a

electricity generator dynamo connected up to a large demonstration ammeter, set up so that a twist of the dynamo

gives a flick on the ammeter. Demonstrate a wind-up radio that give a pulse of radio reception if

the handle is rotated a couple of turns. Ask the students how to get electricity all the time? The

answer to keep rotating the dynamo. What do students consider ways to keep this turning as

much as possible? Elicit ideas to put a propeller or turbine on the shaft. If possible, demonstrate

a rotating turbine in the steam from the spout of a boiling kettle. (b) Emphasise that dynamos

and generators can come in all sizes. There is an alternator in a car, generators for camp-sites,

and huge generators in power stations but they are all similar in design. Use a model generator

to show the copper turns that rotae with the shaft.



Understand that electricity can be (a) Move a thin copper rod in a the magnetic field of strong horeshoe magnet. A sensitive

made to flow by causing movement in ammeter connected across either end of the wire will show a flick of electric current. Note that

an electrical generator when the wire is stationary there is no current and movement is essential. Also, note that the

faster the wire is moved the bigger the flick on the ammeter. Demonstrate that the same effect

is noted if the magnet is moved relative to the wire. This is the work of Michael Faraday. Ask

the students working in groups, to design a way to make it easier to move the wire in the

magnetic field. Discuss their designs and show a cross-section of a dynamo or starter motor,

highlighting the coils of wire neatly arranged around the shaft so that they move when the shaft

is rotated. Note that the magnetic field is often not made by a permanent horseshoe magnet but

it is produced in another set of coils instead (but that's another story...). (b) Use a wind up radio

to investigate how long the reception lasts for a certain number of turns of the handle and/or

turning rate.







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Understand that electricity cannot be (a) Ask the student what electricity is. 'Electricity' has no particular meaning in science, but it is

stored and is generated on demand important that students do not think of it as being used up like a pile of money. In that case their

would be no need for a circuit. It isn't possible to have an 'electricity store of energy', it just is a

way of transferring energy from store to store. It is, however, possible, to have an 'electro-

magnetic store of energy' of which batteries and capacitors are two examples but both of these

devices are only viable for small scale storage. It is not possible to store excess energy on a

large scale by charging capacitors and batteries. (b) Explore what is meant by the National Grid

and how it store energy using hydro-electric power. Inform the students that the demand for

electric current varies. At what time of day and year is there the most demand and why? During

times of high demand, water is let out of dams to drive hydro-electric plants.



know the difference between useful (a) Recall that most power stations work using steam. The steam of made by using fuels.

energy and wasted energy Consider what happens to the steam after it passes the generator and show pictures of cooling

towers. Inform the students that in times of low demand the generators can be switch off and all

the heat goes up the chimney and heats up the air. Ask the students if they consider this to be

wasted energy. Elicit ideas that it is wasteful because the energy that goes up the chimney is

not useful to anyone. (b) What are the students' experiences of patio burners? Do they

consider these to be wasteful for energy and discuss whether it is important to worry about

wasting energy? (c) Sometimes energy can be wasted because it is not in the form that you

want it. Can the students think of any examples? Demonstrate a filament light bulb and note

that it is hot, ask what is the useful form of energy and the wasteful form.



know that during energy transfers (a) Use a BIG pendulum, suspended from the ceiling and a volunteer. Pull the pendulum bob of

energy may go to waste the nose of the volunteer and let it swing. Despite the fears of the volunteer, the bob will not

swing back onto their nose but it's swing will progressively diminish in amplitude. Establish with

the students that some of the energy has been lost from the system with each swing, it is

'wasting' energy each time and less and less is useful to make it swing.(b) Energy efficient light

bulbs often state the equivalence to filament bulbs eg 'this 20W bulb is equivalent to a normal

100W bulb'. Ask the students what the other 80W are doing in a filament light bulb. Encourage

ideas that the light bulb is 'wasteful' because it gives off heat. Draw Sankey diagrams for the

two bulbs where an arrow splits to show the proportion of the output energies. Consider other

devices that transfer energy and where they may produce wasteful energy.



Understand ways in which energy (a) Provide information about the major energy loses in a home and their proportions of total

waste can be reduced loss, eg through roof 35%, through windows 20% etc. Discuss what could be done to prevent

heat loss in each case, eg loft insulation, curtains etc. Also provide information about the cost to

install these energy saving measures and their annual payback. Calculate which are the most

cost effective. Produce a leaflet, giving impartial advice about what people could do to save fuel

bills. (b) Broaden the issue to looking at use of energy in different ways, eg ask pupils to

consider how environmentally friendly electric cars really are. (Although electric motors are

three times as efficient as internal combustion engines, the electricity has to be generated first.)

Compare battery-powered cars (recharged at the mains) with fuel-cell powered models.

Compare the energy required to make a car with the energy needed to run it (ratio is

approximately 10:1). Is the real issue about replacing old, inefficient cars with new, more

energy-conserving ones?



Understand that when energy is (a) A pendulum swing will gradually diminish and many students think that this is evidence that

transferred none is lost energy is not conserved. Similarly, if methylated spirits is burnt, after a while it has gone. What

must be emphasised is that, in both cases, the air has got hotter ie there is an increase in the

stored energy of the air. The total energy, including the wasteful energy, is the same before and

after an event. (b) There is a conflict between the sentiment 'to need to save energy' and the

law of conservation of energy which can cause confusion amongst students. Brainstorm with the

students ways to save useful energy around the home eg double glazing, turning off lights etc.

but emphasise that what is being attempted is to obtain a greater proportion of useful energy.

Illustrate using a Sankey diagram, that the total energy is constant but that there is a split

between useful and wasted energy.





9J Gravity & space

Sub-objective Suggested action SPT relevent slide:

Know that gravity is an attractive (a) Some students believe objects fall simply because thay are heavy. Practice drawing

force acting on the earth towards the situation diagrams where students draw straight arrows, proportional to weight, for various

centre of the planet objects. Encourage students to also draw the earth, so that they can see that gravitational

forces point to the centre of the earth, rather than just vaguely 'downwards' (b) Emphasise that

gravity is an at-a-distance force rather than a contact force by asking them to hang from a beam

and 'feel the force of gravity'. (c) "I throw an object into the air. Are there any forces acting on it

after it leaves my hand?". This is a probing question that reveals that many students commonly

cant accept that gravity acts consistently down throughout the motion. Consider a basketball

shot at stages during its flight. Ask the students to draw force arrows, emphasising that their is

only one arrow, representing gravity, at each stage.



Know that the gravitational pull of the (a) Ask the students to draw gravity arrows on aeroplanes and ask how high the plane would

Earth is strongest nearest the surface have to fly before gravity no longer acted on the plane. Inform them that it would have to 'fly'

much further than the Moon before the arrow would be too small to draw. Show a graph of

gravity strength per kilogram mass against height to show the gravitional pull drops off with

height exponentially. (b) Some students believe that gravity must get stronger away from the

Earth because objects that are dropped from higher up fall with more 'force' i.e. a louder bang.

Indentify students that have this misconception by asking diagnostic questions involving force

arrows at different heights.

Know that the amount of gravity a (a) Show cereal packets that appear to be unopened but have actually had weight inserted.

planet exerts depends on its mass. Students are to lift the normal packet and the heavier ones are what the packet would feel like

on Saturn. Discuss why objects will feel heavier on Saturn, eliciting any ideas that it is because

Saturn is more massive. (b) Some students believe that there is no gravity on the Moon,

because objects 'just float around'. Confront this misconception by showing clips of astronauts

walking on the moon or of objects falling on the moon, emphasising that the Moon does exert a

gravity but it is less than that on Earth. (c) Use secondary sources to find out the weight of 1kg

on other planets. Produce a phamplet advertising 'Loose weight - travel to Mars!' and discuss if

such a phamplet could be produced for other planets.









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Know that mass & weight not the (a) There is a conflict between everday language and scientific language, summarised by 'my

same weight is 55kg', which needs to be addressed. Inform students that this is one of the times that

science language is different from everyday language, and that in science weight is not

correctly measured in kilograms or stones but because it is a force it is measured in Newtons.

(b) Equate to property prices - the cost to build a house is much the same everywhere but how

much it is worth depends on its location. It's the same with mass and gravity. The mass of an

object is the same everywhere but how much it weighs depends on its location. (c) Students to

correct everyday tables that show 'weight' expressed in kilograms, for example tables that

relate amount of pet food to a pet's 'weight'. Ask students why they think so many things are

incorrectly labelled, concluding that some things have become established already and it is

easier just to remember to convert them whenever it is necessary.



Know that weight is caused by the (a) Some students believe that gravity only applies to falling objects. Confront this

force of gravity acting upon a mass. misconception by drawing force arrows on objects in static situations such as books on tables,

emphasising that on Earth all masses are subject to a force due to gravity. (b) Ask students to

lift masses of a known value and feel the attractive force of the Earth's gravity pulling them

down. Emphasise that nobody understands why gravity exists - it is one of the great mysteries

of the Universe. (c) Show pictures of spiralling galaxies and discuss Black Holes as regions in

space where gravity is so large that everything near gets pulled towards it. Write a descriptive

passage of what it would feel like to enter a Black Hole.



know that on Earth, 10N of (a) Use a spring balance, calibrated in Newtons, to measure the force exerted by the Earth's

gravity on known masses. Tabulate results and discuss a conclusion. Consider what would

gravitational force is experienced by

each 1kg of mass happen if this experiment was carried out in deep space or on the moon. (b) Students to

measure the weight of volunteers using bathroom scales measured in Newtons and convert

back to calculate their mass measured in kilograms. Use a conversion chart that converts

Newtons to the imperical measures of stones, pounds and onces. (c) Produce a large wall

display showing pictures of objects such as cars and animals, with their mass, in kilograms,

written next to them. Pin on cardboard arrows representing weight onto the pictures. Use a

consistent scale eg 1N = 1cm.

Know that mass does not change but (a) It is acceptable to state that mass is the 'amount of stuff in an object'. Imagine floating in

weight can. deep space and ask the students if they weigh less and then ask them if there is any less 'stuff'

in their bodies. Draw diagrams of spacemen on Earth and in deep space, arrows may be drawn

to represent weight but mass is a scalar quantity that has no direction associated with it. (b)

Show video clips of spacemen floating in space eg www.esa.int/spaceflight/education. Ask the

students if they are closer to the Earth than the Moon is? The moon is pulled around in an orbit

due to gravity, so how come the spacemen appear to be weightless? The answer is that they

are not in fact weightless but appear to be weightless because they are constantly falling. (c)

Ask students to sketch, on a mini-whiteboard, to draw a graph of mass against distance from

the centre of a planet. It should be a straight horizontal line. Ask if a graph of weight against

distance from the centre of a planet would look similar.



Understand that distance is a factor (a) Look at video clips of the Space Shuttle lifting off from Earth into space. Consider where the

that influences gravity. rocket seems to burn most fuel and inform the students that when in space, it doesn’t use fuel at

all. Discuss why the rocket needs less and less fuel as it gets higher, eliciting ideas that its

weight becomes less. (b) Some students believe that gravity must increase with distance

because the distance to far away planets is so big that it must need a bigger force to keep them

in orbit around the Sun. Confront this misconception by asking the students diagnostic

questions, such as drawing force arrows on the planets due to the Sun's gravity. Emphasise

that even a small force acting over a long period of time can pull a planet in an orbit. Relate to

light intensity that gets less with distance from a source. (c) Introduce the concept of a 'field' ie

any region in space where the effect of gravity is felt. The field strength rapidly decreases with

increasing distance but astronauts are still in the Earth's gravitational field even on the moon

(as indeed is the Moon itself).



Tides are produced because of the (a) Many students believe when it is low tide in the UK, it is high tide on the East Coast of the

influence of the Moon's gravitational USA. Draw contour lines of the height of the Atlantic Ocean when there is a full moon overhead.

field The mass of water gets pulled up in the middle, and the tides on both sides of the atlantic are

low. Empahasise that it is similar to pulling up table cloth in the middle. Confirm this by

comparing tide times on both sides of the Atlantic, correcting for time zone changes. (b) Draw a

picture of the Moon over an ocean of jelly. Draw on a straight force arrow from the ocean

upwards towards the Moon. Label this arrow 'force of gravity due to the moon'. Consider what

will happen to the ocean, eliciting ideas that it would bulge towards the Moon. Consider if the

Earth only was made of ocean, with no land. In groups, the students could draw how the bulge

moves as the Moon orbits the Earth. (c) Project work with titles such as 'where are the biggest

tides in the world?', 'what effect do tides have on fishing?', 'do other planets effect the tide?',

'does astrology have any basis in science?'



Know that the Earth was thought to (a) Using secondary sources, investigate the contributions of Nikolaus Copernicus, Giordano

be the centre of the universe Bruno and Galileo Galilei in shaping our view of the Universe. Illustrate the struggles they had

in having their views recognised. (b) Before satellite pictures, evidence for our position in the

Universe came from studying the motion of stars and planets. Complicated models of motion

are possible to explain the motion of the stars and planets with the Earth at the centre, eg

Ptolemaic universe, but a sun centred model is much more simplistic. Consider why powerful

authorities such as governments and religions insisted on an earth-centred model



Know that the Earth was thought to (a) Some students when asked to draw the Earth will draw a circle and will draw people and

be flat clouds correctly, but when asked to draw rain and hair they will fall to the bottom of the page -

although they will tell you the Earth is round they do not actually believe that gravity acts

towards the centre of a planet but instead it acts downwards. Ask students to draw force arrows

for objects in Australia to elicit their starting point. (b) The horizon at sea seems flat unless it is

viewed from a considerable height. Write a passage descirbing the bravery of explorer's like

Christopher Columbus who set off to sea, with many believing he would sail off the edge of the

world. (c) Use an time line to show the historical breakthroughs in thinking including the

lifetimes of Ptolemy, Copernicus, Galileo and Columbus









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Know how our understanding of the (a) Research the Ptolemaic theory of predicting the motion of the planets. It was very accurate

solar system developed but the Sun-at-centre or 'solar system' theory displaced it because essentailly it was a much

simpler, less convoluted theory. Appreciate that that science from ancient times is not neccarily

crude in its content and approach. (b) Show satellite photographs of the solar system and of

artist's impressions of planets. Inform students that looking at Pluto is like trying to study a dust

particle half a mile away, and that information about planets is still sketchy. It is important that

students appreciate the huge scale of the solar system and that our understanding of the solar

system will remain incomplete. Even travelling at 50000 mph it would still take 50000 years to

reach the very edge of the solar system. (c) Research the objectives and data returned from

Mariner satellites around Mars, and more recently the Cassini-Huygens probe around Saturn

and the Galelileo probe around Jupiter. Consider the enoromous cost of such programmes and

discuss whether the expense is justified.



Know that the moon is a natural (a) Agree that the Moon orbits the Earth in a circle but question who thinks it is a satellite? The

satellite of the Earth definition of a satellite is any object that moves around another object, so the Moon and

Metosat (the weather probe) are satellites of the Earth, and the Earth is a satellite of the Sun.

Ask the students to list other examples of satellites and what they orbit around. (b) Consider the

spelling of the keyword 'satellite', inventing a mnuemonic to help remember.



Know that the orbits of planets/moons (a) Demonstrate swinging a bucket of water around in a circle. Ask: 'What is the direction of the

are roughly circular force?', concluding that there is nothing pushing the bucket around, only the tension in the rope

pulling it around. Many students believe that: 'something must keep satellites going. Don’t thay

have big rockets that push them around their orbit?'. Highlight this as a misconception and that

the only thing keeping a satellite going around is the force of gravity. (b) Draw the solar system

using drawing compasses. Emphasising that the scale between the planets cant be consistent,

or else the circles for the outer planets would be way off the page. Sketch on the elipitical orbit

of Neptune and of comets to highlight that some orbits are not circular. (c) Use an animation to

show the simultaneous motion of Earth orbiting the Sun and rotating at the same time, and of

the Moon orbiting the Earth and rotating at the same time. Emphasise the difference between

'orbiting' and 'rotating' or 'spinning' about an axis.



Know what an artificial satellite is. (a) Discuss with the students what they consider to be 'artificial' satellites - they are man made.

Refer to Arthur C Clarke, the science fiction writer, who first proposed the idea. Research the

history of Sputnik 1 and Telstar, trying to give an idea of the competitiveness between the USA

and the USSR at the time. (b) Consider with the students this statement: 'something must keep

satellites in the air because they are heavy - after all, aeroplanes have big engines and wings

don’t they!'. In fact, Sputnik was about the size of a basketball, but none of the satellites require

engines. Demonstrate this by swinging a bung around on a string, so that it goes around in a

circle. The bung does not have any engines but it is going in a circle. Satellites are pulled

around in a circle by gravity, the speed of the satellite has to be just right so that it neither

spirals into the Earth or is lost in space. (c) Research how many artificial satellites are in space.

Consider what is to be done with them when they are no longer any use - do we have a

responsibility to tidy up our space rubbish?



Interpret simple data about satellites (a) Satellites have to orbit in a great circle about the Earth i.e. the plane of their orbit must pass

through the centre of the Earth. Orbiting above the Earth in a kind of halo orbit is not possible.

To emphasise this draw a satellite orbiting the Earth, without drawing motion arrows, and

consider the force arrows on the satellite. There is only one and that is towards the centre of the

Earth. Since satellites do not have engines, their speed is fixed depending on their height above

Earth. Satellites that orbit closer to the Earth move faster. (b) Some satellites take pictures of

the Earth and so the data that they transmit will depend on the resolution of the camera.

Compare the resolution of digital cameras from a catalogue - what does 'resolution' mean? (c)

Research 'Galileo', 'Cassini' and 'Megallan', which are artificial satellite around other planets.

What information are they gathering?



Understand the use of satellites in (a) Find examples of how satellites are used now in communications, weather forecasting,

simple contexts business, agriculture, resource management transport and science by clipping relevant articles

in magazines and newspapers or from a collection of website addresses (ESA and NASA).

Start a satellite wall display showing why satellites are considered to be increasingly more

useful to mankind. (b) Model how GPS systems work by positioning three stationary students in

corners of the classroom, representing satellites, and a forth student representing a car. By

calculating the time for a signal to travel from the satellite to the car, and by knowing how fast

the signal travels, it is possible to calculate the distance between the a satellite and the car.

Use a fixed length of string from one of the 'satellite' students to the 'car' student. Show that the

car could be anywhere on the radius. By combining with distances between the other 'satellite'

students and the car it is possible to fix its position. (c) Show Google Earth. Zoom in to

locations of interest, emphasising that the images have been made from satellite photography.



Know that satellites have different (a) The two most useful orbits are geostationary and polar orbits. Geostationary orbits are

orbits depending on their function positioned above the equator and are at just the right height to keep above the same spot on

the Earth. There is only one possible distance for a geostationary orbit and this is getting full.

The other useful orbit is polar where the satellite crosses above both poles and so can not be

above the same point on the Earth. Demonstrate the two orbits with a globe and table tennis

ball. Note that stellites in polar orbits will travel faster if they are closer to the Earth so the

images it produces are of less resolution than a geostationary satellite and there are times

when it is on the other side of the world. (b) Refer to old fashioned flash photography where the

subjects had to remain stationary for a few moments and explain that as much light as possible

had to enter the camera. Emphasise that the same is true of the digital camera and discuss

what is needed for high resolution satellite images.









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Know that the Sun is large & exerts a (a) Show that the gravitational effect of the Sun is felt over huge distances by researching the

very large gravitational force keeping Oort Asteroid Belt, which is considered to be the edge of the Solar System. In particular the

the planets in orbit huge distance it is from the Sun, but emphasise that asteroids still orbit the Sun due to its

gravity. Consider what the Sun would look like from these distances. Similarly, consider

Halley's comet, which travels vast distances from the sun before it is pulled back and returns to

orbit at a much closer distance every 76 years. (b) Some students believe that gravity must be

stronger if it is to pull distant planets into an orbit. Emphasise that gravity is considerably

weaker for distance planets but it is still there and does still have an effect. (c) Swing a bung on

a string around in a circular orbit and discuss the forces on the bung. Draw situation diagrams

of the planets and the Sun, showing that there is only one force on the planets and that is

towards the the Sun. Consider why the plants continue in a circular orbit and do not move closer

to the Sun.





9k Speeding up

QCA objective Suggested action SPT relevant slide

Know that if you travel faster you (a) Working in small groups the students compete to see who can come up with the most words

travel a fixed distance quicker or phrases that describe 'speed' eg 'lightning quick' or 'fast as a bullet'. Discuss how their

answers could be ranked - which has the highest speed? Then introduce the idea of speed as a

measure of the distance travelled over time. State that speed doesn't necaessarily mean fast.

(b) In groups, the students sort cards of pictures of animals into groups of fast, medium and

slow. They then have to identify cards that they found difficult to place or justify their groups. (c)

Students match pictures of moving objects with cards with values of distances travelled each

second and compare work with others.

Know that that speed is distance/time (a) Focus the students attention on the idea of speed, where it occurs in everyday life and what

units it is measured in by showing pictures of different examples examples of speed limit signs.

(b) Consider speed cameras that measure the time it takes for a vehicle to travel between lines

marked on the road. Ask if the students have noticed these lines and discuss how the speed of

the vehicle could be calculated. (c) Watch video clips of fast moving action eg athletics, car

racing. Discuss how the speed of the moving object could be measured. What measurements

would they take? Use the clips to measure the time, estimate the distance and calulate the

speed, considering the units.

Knows the units of speed as m/s (a) Estimate the speed at which a caterpillar walks, fingernails grow, jet planes move at etc.

Listing the various units and emphasise that in each case the speed is quoted as a distance

divided by a time. Think of other possible combinations of distance and time and ask what

these units could be used to measure! Introduce metres per second as the unit of speed that is

used most commonly in science. Pay attention to the word 'per' and consider what it means. (b)

There are different notations for the units of speed (eg mps, m/s, ms-1) which can often confuse

students. Find out what units they have been used to seeing in mathematics. Confront the

problem with the students and agree which one makes the most sense. Show the relationship

between distance/time and metres/second (c) Many students think that a bigger number means

faster eg 60km/h is faster than 40mph. It is important to emphasise to students the importance

of units. Illustrate this by looking at different units in the context of another quantity eg height.



Know that average speed is the total (a) Draw a large equilateral triangle. In the bottom left-hand corner write 'average speed', in the

distance divided by the total journey top corner write 'total distance travelled', and in the right-hand corner write 'total journey time'.

time Students to make their own copy on card and use it as a reminder of how to calculate average

speed by placing their thumb over the top of 'average speed'. (b) In threes students measure

the time for a student to run 20m and then a further 20m. Two of the students have stopclocks

that they both start when the third student starts to run. The 'timers' are positioned at the "0m

and 40m marks and stop their clocks as the runner passes. They are then to discuss if the

student run the first 20m faster than the second by comparing times. Inform them that average

speed is total distance divided by total time. (c) Taking it turns students compete to blow a

marble around a race track. Tabulate and calculate ave speed on a spreadsheet. Ask the

students where they lost time and relate to how that effected their average speed.



Know that average speed takes into (a) Refer to a speedometer and ask what it is actually measuring. The answer is the speed of

account variations in speed that occur the wheels and it is an instaneous speed. Compare the expression 'instaneous speed' with

over the course of a journey 'average speed'. Elicit what the students believe the difference is and ask them to give

examples. Agree a contract with the students that you (the teacher) will also say either 'average

speed' or 'instaneous speed' rather than just 'speed' when teaching. (b) The idea of average

speed can be highlighted by first asking the question: 'if Pedro travels 40 miles in an hour, how

fast is he going?'. Students will probable reply 40 miles per hour. Then relate to a real journey,

where the car stopped at lights etc. Say this journey also took an hour to travel 40 miles - how

come? Elicit from them the idea that speeds are often not steady but the average speed

includes periods when the car was moving faster and slower than the average. (c) Compare

distance-time graphs for walkers and runners.

Calculate speed from distance & time (a) A circus of events such as trolleys on an incline; bubbles rising in a water column, paper

helicopters. Students have to calculate the speed of objects. Students could then rank in order,

appreciating that speeds can be compared even if distances are different. (b) From a suitable

viewpoint, students to calculate the speed of vehicles passing along a road. Discuss the

measurements that need to be made and devise a strategy for surveying average speeds along

the road. A series of video clips of cars can be found in the Institute of Physics' Supporting

Physics Teachers CDs. (c) It is often fruitful to approach the mathematics department of a

school and see what overlap there is with teaching this subject. Also, the mathematics

textbooks have a large number of repetitive practise questions.



Calculate distance from speed & time (a) Algebraic manipulation of formulas is recognised as a major problem for many students.

Display the word equation speed=distance/time and then issue the students with a series of

true or false statements such as: 'A man walking at 8m/s will travel 16m in 2 seconds', 'A car

travelling at 100m/s will travel 1000m in a minute'. Discuss if any of the students used a form of

the equation to derive their answers, and if so what was it? Take students through simple

comparative relationships eg 20metres in 2seconds is the same as 10 metres each second.

Establish the equation distance=speed xtime. (b) Try to avoid teaching using symbols instead

of the words. In many textbooks, distance can be represented as an 's', or 'x' and speed as 'v'.

Also when rearranging equations it is good to keep track of the real quantities involved with

early learners. (c) Estimate the speeds of aircraft, ships and cars and convert to metres/second

using a conversion chart. set questions such as if the car had enough fuel to continue at that

speed for 5000seconds, how far would it travel in this time?







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Interprets distance/time graphs (a) Visit http://phet.colorado.edu/web-pages/simulations-base.html and download the Moving

Man for an interactive animation that plots graphs simultaneously as a man moves. (b) Arrange

the members of the class at equal distances around a playing field and issue each with a stop

clock. A volunteer runs passed each student and they record the time from the start to the time

that they pass. Tabulate all results on a class board and then ask students to graph the results.

Inspect the graphs and ask the students to draw lines of best fit asking what their line of best fit

shows. Repeat with another volunteer and compare the graphs. (c) Race a woodlouse or a

maggot down a race track made between two rulers. Record the times to pass each 10cm and

plot these times on a distance-time graph.



Interprets speed-time graphs (a) 'Multimedia Motion', CDrom by Cambridge Science Media, has many clips of various

motions that can be paused and various graphs can be plotted. It is possible to compare

distance-time, speed-time, and acceleration-time graphs for the same motion (b) A team of

students to measure the time taken for a trolley to pass various points on a ramp. Speeds are

calculated and the results are plotted on a speed-time graph. Repeat with differnt angles of the

ramp and compare graphs. (c) Introduce the term 'accelerate' ask students what they

understand by the term. Show a speed-time graph for a falling object reaching terminal velocity

and discuss which parts show acceleration.

Know that an applied force can cause (a) It is counter-intuitive to think of friction-free environments. If a force is applied to a heavy

a change in speed box, it doesnt always move! This applet, http://phet.colorado.edu/web-pages/simulations-

base.html. Forces in 1 dimension, shows a gradually increasing force eventually overcoming

friction and then accelerating the body. (b) Demonstrate a trolley with srings attached to either

end and to equal weights hanging either end of the bench. The trolley will stay put until one of

the strings is cut. Before this, ask the students if there will be a resultant applied force and what

will be its effect. (c) Imagine riding a bicycle and lifting your feet off the pedals. Describe the

motion. Does the bicycle stay at a steady speed forever? If it changing speed, what is slowing it

down? Relate to a sdiagram of the situation and draw on a force arrow representing resistive

force (friction + drag)



Know that an object continues at a (a) It is common sense, though not correct, to think to keep an object moving at a steady speed

steady speed unless a force acts on you need a driving force. It is important to separate the initial force that started the motion, from

it. any subsequent forces which might be present during motion. Consider firing a gun. Does the

bullet speed up after leaving the muzzle? No, it achieves a speed during the explosion.

Consider throwing a book along a desk. Does the book carry the throwing force with it? In this

way, the initial event that got an object up to speed can be shown to be different to the

subsequent motion. Ask the students to think of similar examples (b) Video clips of the sport of

curling are useful to show motion in a low friction environment. Look at the clips, deciding where

force arrows could be drawn during motion. Discuss the motion and the arrows if curling was

played on grass. (c) Imagine maintaining a spaceship and throwing a spanner into space.

Describe the motion. Would it speed up or come to rest? What forces are acting on it after the

spanner as it leaves your hand?

Know that a greater force will cause a (a) A trolley with string attached to one end and to a weight hanging over the edge of the bench,

greater change in speed to a moving could be used to demonstrate the effect of more force on speed. Agree with the students that if

object the trolley, starts from rest, and then travels the same distance in a shorter time then it must be

change speed more quickly. Also agree that changing the weight will effect the driving force,

and ask the students to investigate the effect of greater force on change in speed. (b) Relate

vehicle engine sizes to publicised 0-60 mph values. Tabulate results and conclude that a larger

driving force results in a shorter time to get to 60 mph. (c) Some students will find it confusing

that a car has to exert a greater force to get up a hill but the speed doesnt increase, or that the

same force can be applied to different masses and result in different changes in speed. It is

important to stress that in everyday world there are often other forces that complicate the

picture and the mass of an object is important. Issac Newton was so clever because he

managed to work it out despite all the confusion of everyday experience.



Know that friction opposes motion. (a) Some pupils believe that friction is only associated with moving objects and some that it is

only associated with stationary objects. Ask the students if you are experiencing friction when

you stand and when you walk. Secure a sandpaper strip onto a ramp and place on top a

sandpaper block. Gradually increase the angle of the ramp amd discuss why it doesnt move at

first. Elicit ideas that the grains of sand lock together up to a point, and that there is a force

resisting motion. It is important for students to realise that friction is not a phenomenon, just the

name given to the resisting force. (b) Inform the students that even apparently smooth objects

have rough surfaces when looked at under a microscope and ask them to draw two rough

surfaces in contact. Demonstrate gradually increasing the force to a sandpaper block on a flat

sandpaper surface. Discuss the size and direction of the friction force before and after the block

starts to move. Compare ideas with pushing a smoother block over a smother surface. (c) Ask

the students to write a story 'the day in the life without friction'.



Know the factors that increase or (a) An elastic band catapult can be used to slide a 100g mass along a table top. A class

decrease friction. competition could find the group that could slide their coin the furthest. Discuss the reasons why

they won (more force, smoother surfaces). To make it a fair test, keep the force the same and

investigate the effect of putting some olive oil of the table. Ask what effect theoil had on friction.

(b) Before a curling match water is sprayed on the rink. Why is this? The answer is that the little

bobbles of ice that are formed reduce the contact area between the ice and stone and so the

stone has even less friction. In fact, to slow down the stone as it approaches the target these

bobbles are swepped away to increase the friction. Use this information to deduce that contact

area is important factor in the amount of friction. Reinforce by showing a worn brake pad from a

bicycle and ask why its no good in terms of friction and its function. (c) Demonstrate increasing

the angle of a ramp until a block starts to move. Ask the students to predict what would be the

result if a heavier block was used? Students investigate their predictions.









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Interpret information about friction (a) This applet http://phet.colorado.edu/web-pages/simulations-base.html. Forces in 1

from motion experiments. dimension, can be used to record limiting friction values on a number of different objects. (b)

Students to perform investigations into the frictional force associated with pulling a shoe with a

forcemeter. Find the force to just make a shoe move and investigate the effect of putting weight

into the shoe. Compare with different shoes and discuss why some shoes are disgned to have

high friction. (b) Consider the force arrows on a block of wood that is being pushed along a

table. Gradually increase the force and ask what the value and direction of friction would be

before it moves, as it is moving with a steady speed, and as it is being made to speed up. Ask

students to draw force arrow diagrams for each of the three situations and closely inspect their

work. (c) Roll a trolley down a ramp and measure its stopping distance. Students to investigate

the stopping distances on different surfaces eg paper, carpet.



Know that air & water resistance (a) For many students air is nothing. Remind them of a really windy day and imagine what it

increases with increasing speed would be like to stick your head out of a sunroof of a moving car. 'Why do you think that we call

air resistance?' and, as a class, summarise its properties eg. it gets bigger as the car moves

faster, it slows you down, it depends how big your head is. (b) Ask students to suggest why

streamlining is important for fast-moving fish. Why does streamlining help an athlete to run or

swim faster. Write a radio advertisement for a streamlined car, explaining the advantages that

streamlining brings. (c) Imagine cycling home in cold rain. The particles of rain hit more often

the faster the cyclist travels. In this way, relate to air and water being made of molecules that hit

an object more often the faster it goes.



Know how to draw & label two forces (a) Take the students out for a tug-o-war competition. Establish two even teams and then

acting on an object. unbalance the teams by asking one or two students to join the other team. Draw the situation

diagrams so that the students can see and ask them to stick the correct sized carboard arrow

onto the diagram. Conclude that the correct force arrows could even help us predict the

outcome of a tug-o-war event (b) Many students are sloppy when it comes to drawing force

arrows and, of course, the teacher should always give a good example. They should be

straight, proportional in length to the size of the force, and acting from the object. If students are

finding drawing arrows difficult, then card stencils of arrows of different lengths could be used.

(c) Show to the students that forces are there all the time but they can only be seen with Force

Spectacles.Remind them that the force of gravity is there all the time. When the sunglasses are

worn then force arrows can be seen on objects. While a volunteer is putting them on, add

cardboard arrows to everyday objects. Joke with the class that there isnt enough arrows for

everything so we'll have to be selective when we use them.

Knows that a change in speed is the (a) To many students it is counter-intuitive to think of friction-free environments. This applet,

result of unbalanced forces. http://phet.colorado.edu/web-pages/simulations-base.html. Friction in 1 dimension, shows a

gradually increasing force eventually overcoming friction and then accelerating the body. The

animation shows force arrows cancelling out up to a point and then, when motion occurs, the

resultant force is greater than zero. (b) Some students persist with the idea that for steady

motion to be achieved that the driving force must be slightly bigger than the drag/friction forces.

Pursue the idea that a even a small inbalance will cause the object to change speed but it may

be while before that change in speed is noticed eg a comet has a small force acting on it but

eventually it picks up speed as its passes the Sun. (c) Draw a situation diagram of a tractor

pulling a load. Discuss what would happen to the speed of the tractor if the load fell off.

Students to draw a wall display explaining the situation without using any written words.



Know about the effect of balanced (a) Inform the students that objects are either moving at a steady speed or at a changing speed.

forces acting on objects Pose the question: 'well, what if I have no speed?' and inform them that it is important to realise

that if objects are still then they are said to have a steady speed of zero. (b) Imagine you are

travelling in along a motorway in a car. Does the driver need to have their foot on the

accelerator all the time? When you are travelling at 50 mph, does the driver need their foot on

the floor all the time? If the car ran out of petrol would it suddenly stop? Why does it say the

most economical speed for my car is 56 mph?. Use these questions to elicit student ideas

about motion, leading them to conclude that for steady motion all that the engine need to do is

overcome friction. (c) Consider the forces on the curling stone in a vertical direction -its not

rising or sinking even in motion, so what can be said about the resultant vertical forces? The

resultant force in the vertical direction must be zero (i.e. weight is equal and opposite to the

reaction force)

Intrepret acceleration and (a) The students in groups, consider a choice of pre-drawn graph shapes. Ask them to pick the

deceleration from a speed/time correct graph shape for a falling object, and then ask them what their graph axis represented.

graph. 'What would be the graph shape if the axis were speed against time and what would its general

shape look like if the axis were acceleration and time?'. (b) An applet show graphs being

simultaneously constructed at the same time as motion can be found at http://www.walter-

fendt.de/ph14e/acceleration.htm. (c) Consider a speed/time graph for a car journey. Use the

graph to answer questions such as: 'At what times did the car speed up and slow down?'



Understand the various stages of a (a) Students have to appreciate that objects accelerate as they fall under gravity, but also to

parachute descent. recognise that they may achieve a terminal speed due to drag forces. Imagine the experiences

of a skydiver. First they speed up, gravity pulling them down with a constant force, but as they

fall, the wind in their face gets stronger and stronger. They may reach a velocity when the

downward weight is equal but opposite to the drag force. At this point ask the students what the

resultant force is and what would happen to their motion. Some will argue that they should stop

if there is no force - but clearly this doesn't happen! When the parachute is opened, suddenly

the drag that such a large canopy produces unbalances the forces, the resultant is upward and

the skydiver's descent slows down. Note there are two possible periods when the velocity is

constant, the second as a skydiver slows to a point when the drag again is equal and opposite

to the weight. (b) Investigate terminal velocity by timing ball bearings to descend in a tube of

wallpaper paste. Mark the tube at regular intervals and challenge the students to find when the

ball bearins started to fall at a constant speed..

Interpret graphs of parachute (a) Provide the students with data of speeds at various stages of a parachute descent, including

descent. speeds before the opening of the parachute. Students to construct their own graph and label

stages. Writing an account of the descent as if they were giving commentary they are to

describe what if feels like at the various stages of the descent (c) Students drop model

parachutes and toy people and observe the descent closely. Time how long to takes and

compare with different size parachutes or weights. Students to draw graphs for each descent

and present their work.



Unit 9L Pressure and moments

sobj Suggested action SPT relevant slide





Page 27 Based on QCA objectives

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Recognises that pressure = (a) Relate to the students that as part of their training as scientist thay have to realise that, in

force/area science, some keywords have a particular meaning. Ask the students to write as many

expressions as they can that include the word 'pressure'. Use their answers to form groups.

State that in science, the word pressure only means one thing and that is force divide by area.

(b) Ask the students to push themselves in the chest with a flat hand and then a pointed finger.

The force was about the same, but why did the poking finger hurt more? Elicit ideas about the

force being 'concentrated' to a point, and write sentences that explain the experience using the

words: pressure, force and area. (c) Deflated bike tyres have more area in contact with the

floor. It is worth associating the pressure of air and the pressure that the tyre makes with the

floor. 'If I remove air from the tyre and decrease the pressure inside, what happens to the tyre?'

Elicit ideas that it flattens out because of the weight of the bike and associate increasing area

and decreasing pressure.

Able to apply qualitative assessment (a) It aids understanding to emphasise that pressure is a scalar quantity ie it should not have an

to pressure situation arrow associated with it. Forces act on objects in particular directions, pressure is just a useful

measured quantity. (b) Show a brick to the students and challenge them to position the brick so

the pressure is at its lowest value and at its highest value ie. balanced on its end. Explain why

they have chosen those positions. Emphasise that the weight of the brick has not altered. (c)

Ask how students could survive if they walked into quicksand. Many will know the advice to

spread out but ask them why, challenge them to use the expression 'force on each unit of area'.

Draw two situation diagrams showing a person lying down and standing up. On each diagram

position 5 cardboard arrows, each representing 10N. In the case of the person lying down they

are spaced out but in the case of the person standing the arrows overlap to act only at the feet.



understanding the units for pressure (a) There are several units for pressure such as, 'bar' and 'pounds per square inch'. Show

pictures of different pressure readings such as weather maps and footpumps. Agree that it will

be easier if we only use one unit in science. Refer to the equation, pressure=force/area and

recall the units for force as 'Newtons' and the unit for area being 'square meters'. Challenge the

students to derive the standard unit of pressure as Newtons / square metre. (b) It is a common

confusion amongst learners to mix the 'number of square metres' and the 'number of metres

squared' eg a 2x2 metre square board has an area of 4 square metres but to state 4 metres

square implies 4x4. (c) The standard unit for pressure can be represented as N/m2; Nm-2 or

Pascals (Pa). It is a source of confusion for many students and so it is advised that in teaching,

you use the full words whenever possible ie. Newtons on each square metre, to give a feel of

the use of pressure as a quantity.



doubling or halving force over (a) Display the equation pressure=force/area and input some figures. Keep the area value

constant area constant (but not equal to 1) and calculate the pressure values for different forces. For each

case try to get a picture of the physical situation by saying pressure has a value the same as 'so

many Newtons per square metre'. (b) Use a tray of sand and a square of chipboard. Students

investigate the depth of indent against load on the board. Discuss results and conclude as a

group. Elicit ideas that the value of pressure has doubled when double load is added and as a

consequence the indent is deeper. (c) Describe a scenario where an indian tracker can tell

whether a horse carries two passengers or none at all by looking at the hoof prints. Discuss

how the tracker could know and relate to a scientific experession relating weight and the

resulting pressure value.

pressure = force/area (a) Some students will understand an equation better by inputting numbers rather than letters.

Display the equation pressure = force/area and input some numbers. Keep force value

constant, say 10N, and calculate the new pressure when the area is altered (b) Use a

mnemonic to help remember then equation pressure=force/area such as 'pantomime equals

food over the areana' (c) As a homework, research the science meaning of the word 'stress'

related to materials. Ask students to identify the difference between the word 'stress' and

'pressure'. It difference is that stress has a direction associated with it but pressure is a scalar

quantity

describe some effects and uses of (a) Some students believe that gases are too 'thin' to have a pressure value. Show the Gas

gases under pressure Properties applet found at http://phet.colorado.edu/web-pages/simulations-base.html to

visualise why gases exert a force on the walls of the container (b) Introduce the word

'pneumatics'; ask about experiences of gases under pressure, eg bicycle tyre ('pneu' is french

for 'tyre'). (c) Demonstrate a model steam engine and show how useful machines can be made

by increasing the pressure of the gas. Ask students to explain why the steam has more

pressure when heated using ideas of particle motion.

describe an effect of atmospheric (a) Heat an opened drinks can and then submerse in water. The can should collapse. Ask the

pressure students to explain, paying particular attention to answers such as: 'the can collapsed because

the vacuum sucked the walls in'. Students need to appreciate that the can collapsed because

there is an imbalance between the force exerted by particles outside the can and the force

exerted by particles inside the can. (b) Show the students of flat fish that live on the bottom of

the sea eg skate, and tell them that we are at the bottom of a sea as well - a sea of air! Discuss

what the effects of living at the bottom of the sea would be for the fish. 'It doesn't notice it

because its used to it' and explain that we dont notice the effects of 'air pressure' because we

are used to it, but on an average table there is a force equivalent to the weight of 5 cars on it!

Students could draw a poster to display this interesting fact. (c) Demonstrate the use of sink

plunger or dent removers that can lift smooth boards. Draw a cartoon strip showing the forces

on the plunger due to air before and after its use.



describe some effects and uses of (a) Offer the students syringes connected by rubber tubing. Fill one of the syringes with water

liquids under pressure, and and the push the plunger to move the water into the other chamber. Consider what use this

could be and ask the students to invent something that could use this effect. (b) Ask a volunteer

to lightly hold a balloon between flat hands. Fill the balloon with water from a tap and ask if the

balloon is trying to push the hands apart. Show pictures of hydraulic machines like big yellow

bulldozers and state these work on a similar principle. Discuss how bulldozers can lift heavy

loads (c) Discuss how remarkable brake systems are on a car - how they can stop a car

travelling fast. Explain that they work by moving brake fluid around and challenge the students,

working in groups to explain how brakes might work. Discuss the properties of the brake fluid -

it is runny, non-compressible and doesnt freeze at normal temperatures - why are these

properties important?









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describe an effect of underwater (a) The pressure in a liquid or gas is the same in all directions. Distinguish between force which

pressure acts in a particluar direction. Remind students of the last time they had their head underwater.

They were not pushed to any direction - the force due to water was the same from every

direction. (b) Elicit sudents' ideas as to why special submarines have to be used to explore the

very deep oceans. What would be the effect of going too deep? (c) Refer to a diver who said:

'The pressure of the water pushes directly on my ear drums' and ask if this statement is

scientifically correct. It is important to distinguish between the words 'force' and 'pressure'. The

pressure causes a force, pressure has not direction associated on it and a force is exerted by

one thing acting on another. Ask the students to rewrite the statement correctly, by substituting

the word 'pressure' for 'force'.

apply the concept of transmission of (a) Some students develop a picture of forces being carried, by the fluid, from cylinder to

pressure to predict the resulting force cylinder. Care is needed not to suggest the force 'slides around the bends' from one piston to

another. Instead make the connection by pressure values. Consider that the pressure

throughout the fluid increases by the same amount when a force is applied to one cylinder and

then the system equilibrates back to its original level and a force can be felt at the other

cylinder. (b) Show students a set up were two syringes of different cross-sectional area are

connected via a rubber tube. Fill one of the chambers with water and push in the plunger so the

water is transferred to the other chamber - this is a simple hydraulic system. Hold both syringes

vertically downwards and add a weight to the small plunger so that the larger plunger goes up.

Vote on how much weight has to be put on the large plunger to push the small plunger back up.

Is it less, more or equal to the weight on the other side. It is counter-intuitive to many but the

large piston will need considerably more weight to push the small piston back up.



apply the model of the particle theory (a) Agitate a tray of marbles and ask the students to listen for the collisions the marbles have

of matter to explain the behaviour of with each other and wall. Distinguish that there are two distinct sounds and try to count the

gases under pressure number of collisions with the walls of the tray only. Discuss how this helps to explain gas

pressure. Repeat with a smaller tray or move one of the slides in, this time there should be

move collisions with the walls in a certain time. Conclude that pressure is increased as volume

is decreased. (b) Use the Gas Properties applet at http://phet.colorado.edu/web-

pages/simulations-base.html. to demonstrate the effect on gas pressure as volume is varied (c)

Role play gas particles in an enclosed room. The particles must obey the rules of travelling in a

straight line, not speeding up and bouncing off each other at a sensible angle. Discuss the

effect of giving energy to the system - the individual particles all speed up. Try to observe that

there are now more collisions in a certain time i.e. the pressure has gone up!



apply the particle model of matter to (a) Ask groups of students to draw on a flipchart how particles are arranged in liquids and

explain why liquids are gases. Discuss answers and ask them why it is easier to compress liquids than gases. (b) Push

incompressible and gases are two sealed syringes, one filled with air and the other with water. Ask why it the air syringe has a

compressible little 'give' in it before it resists the push. (c) Refer to the braking system in a car, showing brake

fluid being pushed from one cylinder to another. Inform the students that brake fluid is a liquid

not a gas - ask why it would be dangerous to use gas in a brake system.



describe how to make a task easier (a) A large demonstration see-saw made from a plank of wood and a log can be used to lift a

by increasing the distance between volunteer with one hand! The volunteer sits at one end of the see saw and the teacher at a

the effort and the pivot much larger distance from the pivot can lift themin the air. Many students will have experiences

of this in playgrounds. (b) Close a door with one finger. repeat at distances nearer and nearer to

the hinges. Notice that it is harder to close the door at a smaller distance. Agree on a

conclusion to record in their books (c) Challenge students to hold a retort stand out in a

clenched fist. Add a bag of weights to the end of the rod and ask them to hold the rod level at

for as long as possible. Then, do the same yourself but this time push the bag nearer the fist ie

nearer the pivot, and you will be able to beat anybody! Explain to the students that there is a

trick involved and they have to guess what it is



identify levers in a number of (a) Students are invited to label photographs of levers so that they can get better at finding the

household devices lines of action, the forces acting, and the pivots. The images could include door handles,

spanner in use, screwdriver opening a paint tin. (b) Encourage students to go on a 'lever hunt' at

the school or at home, identifying where the pivot is in each case with a small sticker (c)

Consider a wheel-barrow and why it makes lifting heavy objects easier. On a drawing of a

wheel-barrow, identify the pivot, the effort force and the load. Discuss whether a wheel-barrow

is a kind of lever.

describe how an object can be kept in (a) Ask students to stand with their heels touching a wall and try picking up a coin placed 0.5 m

balance away. It is impossible to pick up the coin without loosing balance. Discuss what what have to be

done to keep balance and show pictures of a crane with a heavy counterbalance. (b) Ask a

volunteer to lift an object with their arm only so that their bicep bulges. Show a diagram of the

bones and muscles in the are. Indentify the pivot, the effort and load (c) It is important to insist

on accurate drawings of distances and forces when teaching turning forces. The distance is as

important as th size of the force and care should be taken to draw force arrows straight, in

proportion to the size of the force, and acting from the correct point. Other arrows indicating

motion may at some point be drawn on the diagrams so the force arrows should be

distinguished.

apply the idea of the turning effect of (a) Some students may think that levers just magnify a force i.e. that they get something for

a force to everyday situations nothing in a lever. Emphasise that to get a larger force out of a lever, the effort needs to be

further away (b) Look at pictures of steering wheels, large and small. In each, indentify the pivot

as being in the middle. Consider where the forces would be if both hands were on the wheel.

There would be two turning forces, one clockwise and the other anticlockwise. Now discuss why

sports cars have a small steering wheel - it is not just to look good, it is also because it is more

responsive but harder to turn. Relate to experiences driving bumper cars at the fayre. (c) Relate

to experiences of windsurfing, especially trying to bring a sail to the vertical position. When the

surfer is balanced there are two turning forces balanced - can the students identify them?



Describe the turning effect of a force (a) Inform the students that in science the word 'moment' does not refer to time but is a word

as its moment used instead of 'turning force'. (b) Make a mobile for a child's bedroom. Write notes about the

construction using the terms 'pivot', 'balance' and 'moment' . (c) Challenge students to deduce

the unit of a moment. Use the equation moment=perpendicular force x distance from the pivot

to establish the unit is Newton metres (Nm)









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Identfy the direction & magnitude of a (a) Working in pairs, students investigate for themselves the relationship between force and

turning force distance to balance a see-saw. After a period of investigation, students can write their

relationship on a mini whiteboard and compare with others .(b) Relate to experiences of

windsurfing, especially trying to bring a sail to the vertical position. The centre of gravity of the

sail is a set distance from the pivot but the force needed to correct the sail is greater at first

because the force is not perpendicular to the sail (c) Consider a loft trapdoor. The door swings

open and comes to rest in a vertical position. The force that is causing the turning effect is

weight but why no turning effect when the loft hatch is hanging vertically? Elicit answers that the

weight is not in the correct direction to cause turning when vertical.



Simple calculation of moments (a) The applet found at http://www.walter-fendt.de/ph14e/lever.htm is a simulation of a see-saw

which may enable students to establish the relationship between forces and distance. (b)

Calculate the weight of a retort stand by first marking its centre of gravity (or balancing point),

then make it pivot about another point, adding weights to an end to make it balance. The

distance of the centre of gravity to pivot multiplied by the weight of clampstand = to the weight

added multiplied by its distance to the pivot. (c) Tabulate correct distance and weight values for

a balanced see-saw. Erase some of the readings and challenge the students to work out the

missing numbers









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