Physical Science - Download as PowerPoint

							Physical Science

A study of matter and energy
What will we study this year?
   Chemistry
     Properties
     Elements,Mixtures, Compounds
     Atoms, Molecules and the Periodic Table
   Physics
     Forces  and Motion
     Energy- Waves, Sound and Light
     Electricity and Magnetism
        Tools of a Scientist

 Observing        Interpreting   Data
 Predicting       Inferring
 Classifying      Communicating
 Measuring
Let’s Review
   How do we go about finding a solution to a
    problem?
                  Scientific Method
   Observation                    Analyze Results
   Ask a question                     Organize data in chart,
                                        graph, drawing
   Form a hypothesis
                                       Summarize findings
   Design an experiment
                                   Draw Conclusion
    to test hypothesis
                                       Make inferences (possible
       Variables (controls,            explanations why, reasons
        manipulated variable,           for results)
        responding variable)
       Materials
                                   Communicate Results
       Procedure                  Repeat
Let’s Review
   What are the basic components of every
    investigation?
   Controls
     Thingsthat never change in an experiment
     Why do we need them?

 Variables- think DRY MIX
 Manipulated (Independent) X axis
     Variable
             changed in an experiment
     How many can you have in each experiment?

   (Dependent) Responding Y axis
     Variable that responds to the change
     Variable that depends on the other variable
Types of Set Ups
 Control set up- experiment without the
  manipulated/independent variable
 Experimental set up- experiment with the
  manipulated/independent variable
Sample Scenarios
 Determine what question is being tested.
 Identify the controls in the scenario.
 Identify the manipulated/independent
  variable.
 Identify the responding/dependent
  changeable.
   The students sat still for 5 minutes then
    took their pulse for 30 seconds, walked
    around the room for one minute and took
    their pulse for 30 seconds, exercised for
    one minute and took their pulse again.
    They recorded the class data, averaged
    and graphed the results.
   The researchers placed 1 gram of a
    chloride compound in a liter container full
    of water, marked A. Then they placed 2
    grams in one liter of water marked B and 3
    grams in a one liter container marked C.
    The temperature was measured after the
    chloride compound had been mixed for 30
    seconds.
   A net was set up to catch insects. The
    insects were removed, classified and
    counted by groups every 3 hours for 5
    days. The number and kind of insects
    were compared by the time of day they
    were collected.
Experimental Design
 Determine how to set up an experiment to
  test each problem.
 What materials would you use?
 What is your procedure?
 Which brand of floor wax holds its shine
  the longest?
 What effects the growth of tomato plants?
 What is the effect of water temperature on
  the dissolving time of sugar crystals?
             Scientific Theory
   a unifying explanation for a broad range of
    hypotheses and observations that have
    been supported by testing. A theory can
    explain observations and predict future
    observations. Theories can be changed as new
    observations are made.
      Example: Atomic Theory
                Scientific Law
   A summary of many experimental results
    and observation. A law tells you how
    things work. Laws are not the same as
    theories because laws only tell you what
    happens not why it happens. The law tells you
    that you can expect the same thing to happen
    every time.
      Example: Newton’s Laws
Let’s Review
   How do we measure our results?
     The   SI system
What is SI? Why do we use it?
 System International or International
  System of Units
 Metric System
     Decimal  system (base 10, multiples of 10)
     Each unit is 10 times bigger or 10 times
      smaller than next unit
     Very precise and accurate
     Internationally used
Basic Units
Quantity    Unit    Symbol    Instrument
 Length    Meter      M       Metric ruler,
                              meter stick,
                             trundle wheel
Volume      Liter     L        Graduated
                                Cylinder,
                                LxWxH
 Mass      Gram       G       Triple Beam
                                Balance
Weight     Newton     N          Spring
                                  Scale
Prefix       Power of 10    Symbol   Example

kilo-        1000 (103)     k        kilogram (kg)

hecto-       100 (102)      h        hectoliter (hL)

deca-        10    (101)    da       decameter
                                       (dam)
Basic unit   1     (100)    ---      Meter, Liter,
                                       Gram
deci-        0.1   (10-1)   d        decigram
                                       (dg)
centi-       0.01 (10-2)    c        centimeter
                                       (cm)
milli-       0.001 (10-3)   m        milliliter (mL)
   Kids            Kilo
   Have            Hecto
   Dropped         Deca
   Over            Ones (meter, liter,
   Dead             gram)
   Converting      Deci
   Metrics         Centi
                    Milli
Let’s Practice….
4 kg = _____ g
3 km = _____ dam
400 mL = ______ L
3275 g = _______ kg
What about really small things?
 Micro- millionths
 Nano- billionths
 Angstrom- 10 billionths
Let’s Review
   What are some basic properties?
Mass
 The amount of matter in an object
 Instrument-triple beam balance
 Basic Unit= the gram
Weight
   A measure of attraction between 2 objects due
    to gravity
   Affected by mass and distance
     Mass Weight    (direct relationship)
     Distance Weight    (indirect relationship)
   Instrument- Spring Scale
   Unit- Newton
     If   you eat too many fig newtons you will weigh a lot!
   Mass x 9.8 = weight in Newtons
   Weight ÷ 9.8 = mass in Grams
Volume
   A measure of the amount of space an
    object takes up
     Regular  object- L x W x H
     Irregular object- water displacement using
      graduated cylinder
Volume (water displacement)
   Fill cyclinder with water
   Record volume of water (look below meniscus)
   Place object in water
   Record volume of water with solid submersed
    (look below meniscus)
   Subtract volume of water from the solid and
    water combined
   Record results in mL or cm3 of cc
Volume Activities
 10 cm x 10 cm x 10 cm = 1000 cm
 1000 cm = 1000 ml
 Volumania p.9 Lab Book
Mission Impossible Activity
   Examine an index card. Take note of its size
    and shape.
   Your mission is to fit yourself through the card.
   Brainstorm with a partner about possible ways to
    complete your mission keeping the following
    guidelines in mind:
     You can use scissors and you can fold the card but
      you cannot use staples, paper clips, tape , glue or
      anther other adhesive.
   Test your strategy and share your results with
    the class.
Density
 Relationship between mass and volume
 the amount of mass per unit volume
 Mass ÷ Volume or M / V
 g/ml or g/cm3 or g/cc
Density
   Take the mass of an object using a triple beam
    balance, take the volume of object by either
    water displacement or calculating L x W x H.
    Divide mass by volume to obtain the density of
    an object.
   Density of water = 1 g/ml
   If density > 1 , object sinks
   If density < 1, object floats
Density Activities
 Marbles, sand, water
 Alcohol and water
 Orange in water
 Density column
 Chocolate Bar lab
The Case of the Missing Crown
Imagine that you are living in Europe in the
Middle Ages. You have been summoned by
King of your land to help in a very important
matter. Someone has stolen the king’s solid
gold crown. The king has issued a
proclamation offering a reward of 500 gold
coins for the safe return of his crown. The
problem is that the king has received hundreds
of crowns—and they all look exactly alike the
missing crown. Your job as a brilliant scientist
is to find out which crown is the real one.
 Crown #                  Mass (g)                Volume (cm3)
 1                        1890                    180
             you collected
Here is data486
 2                     180
 3                        1404                    180
 4                        3474                    180
 5                        2034                    180

 Density of common metals:
 Gold 19.3 g/cm3                     Aluminum 2.7 g/cm3
 Silver 10.5 g/cm3                   Lead     11.3 g/cm3
 Copper 9.0 g/cm3                    Iron      7.8 g/cm3

 1. What properties can you determine from this data? Why is this useful?
 2. Based on this data do you think any of these crowns could be the real
    one?
 3. Which of the crowns are fakes? Why?
 4. Can you guess what fake crowns are made of?
 5. How do you think the fake crowns were made to look like the real
    ones?
What is a model?
   A representation of an object or system
     Examples:  rocket, atom, weather map, solar
      system, cell, building
Why Use Models?
   Help visualize information that your cannot see
    directly (ex: atom)
   Just the right size (ex: solar system, phases of
    the moon)
   Build scientific knowledge to:
     Test  hypotheses (ex: build a model plane to test wind
      patterns)
     Illustrate theories (ex: atom model)
     Saves time and money (ex: car design for crash test)
Lab Safety
Lab Safety
 For your protection.
 Use common sense.
 Required for every lab.
 Lab Safety Contract.
Lab Safety Symbols
Safety First
   Can you find all of the safety violations in
    the following slide?