# Ed 713 22 Magnet Power Point Presentation 2 1

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```					       By
Mosharraf Hossain
Tamara Shorter
John Heyenga
Ed 713.22/ Summer ’08
Which items a magnet will attract?
Test the items listed below and
Item          Yes         No
Pencil
Paper Clip
Penny
Marble
Scissors
Nuts & Bolts
Yarn
Button
What will make a magnet move?
Item       Yes   No
Pencil
Paper Clip
Penny
Marble
Scissors
Nuts & Bolts

Yarn
Button
Will these items be attracted to a magnet?

yes   NO         yes   No        yes   NO

yes   no         yes no          yes    no
The power of magneti
interaction.
Were you correct? Why were these things
attracted to the magnet?
N                               S
What will happen when the ends of the two
bar magnets are placed close together?

N                   S         N                 S

What will happen when the ends of the two
bar magnets are placed close together?

N                   S         S                 N
The North and South poles of the magnet are
attracted to one another.

N                S   N               S

Like poles of the magnet are not attracted, or
repel one another.

N                S           S                   N
What is magnetism?
• Magnetism is the force of attraction
between magnets and magnetic objects.
Graphic Organizer (K W L H Chart)
What We Know        What We Want to   What We Learned    How Can We Learn
Learn                                 More
They stick to       How do the         Why do they       BY doing hands
refrigerators.      magnets stick      stick to           on activities.
They stick to       together?          refrigerators?    Reading more
metals.             What happens       What metals do     books.
Sometimes they      when you break     they stick to?
won't stick to      a magnet?          Why do some
each other.         How do             ends push
They come in        magnets make       away from each
all sizes and       things move?       other? Why are
shapes. We use                         the ends called
them to hold                           poles? How do
papers. They                           opposite poles
can hold a lot of                      react to each
stuff. Some                            other? How do
ends stick to                          the same poles
each other.                            react to each
Some magnets                           other? How do
have an N and                          we use
an S on their                          magnets in our
ends.                                  homes?
Magnetic Field Lines
Magnetic field lines describe the structure of
magnetic fields in three dimensions. They are
defined as follows. If at any point on such a line
we place an ideal compass needle, free to turn in
any direction (unlike the usual compass needle,
which stays horizontal) then the needle will
always point along the field line.

Field lines converge where the magnetic force is
strong, and spread out where it is weak. For
instance, in a compact bar magnet or "dipole,"
field lines spread out from one pole and converge
towards the other, and of course, the magnetic
force is strongest near the poles where they
come together.
Magnet and Magnetic Field
Electromagnet
• A temporary magnet          • A junkyard is one place to see
made by passing               an electromagnet in action. A
electric current              crane holding a huge
through a wire coiled         electromagnet can be used to
around an iron bar.
pick up scrap metal when
current flows through it. When
the crane operator wants to
drop the scrap, he or she will
Use link below to see a         simply shut off the current to
example of how to             the electromagnet.
make a temporary
magnet.
h?v=gltbfUOf6F0
Students’ results of
electromagnetic testing
Results of Electomagnetic test

Number of Batteries               Number of Nail           Number of wrapes        Paper clips picked up
1st turn      2nd turn        1st turn     2nd turn      1st turn 2nd turn         1st turn 2nd turn
Group 1     0            2               1            1             0         15              0           6

Groput 2     1                1          1             2              10     10              2         4

Group 3      1                1          1             1              15     30              3         4

Group 4      1                1          1             3              13     13              2         5

Results of Electromagnetic test

35
30
25
Group 1
Range

20                                                 Groput 2
15                                                 Group 3
10                                                 Group 4

5
0
2nd

2nd

2nd

2nd
turn
turn
turn
turn
turn
turn

turn
turn
1st

1st

1st

1st

Number                 Number
of    Number     of wrapes Paper
Batteries of Nail              clips
Variables
What is the relationship between
electricity and magnetism?
Electricity and magnetism controls much
of our current technology (e.g. computers).
 Electricity and magnetism are linked
on a fundamental level.
Magnets are used to generate, or produce,
electricity.
Spinning a coil of wire inside a magnetic field
produces an electric force between the ends of
the coil.
In a similar way, an electric current produces a
magnetic field around it.
Magnetic Forces Scavenger Hunt
1) Write three questions for the class from this video.
Experimenting With magnets.

2) Write three questions about different experiments that deal with earth's
magnetic force.
3) Examine the different photos and come up with two questions about Auroras.
The Auroras are connected to magnetic forces.
http://www.exploratorium.edu/auroras/index.html

http://www.educational-games.org/logic_games/magnets.html
Write two questions for the class about what you observed.

Hunt for Magnetism: A treasure hunt on magnetism
http://www.kn.att.com/wired/fil/pages/huntmagnetisma.html

The scavenger sites as well as the treasure hunt site is located on the
filamentality website.
http://www.kn.att.com/wired/fil/pages/listmagnetisma1.html
•   Magnet Song
•   How does electricity create a magnet?
•   Cartoons
•   Mutual Distraction (Cartoon)
•   Underdog Cartoon
•   Magnet Quiz
•   http://library.thinkquest.org/06aug/02337/quiz.htm
•   Teaching magnets to students
Can you name something that is
huge and has
North and South Pole?
• If you answered “The Earth”, you were right!

• The Earth is a giant magnet. It has two magnetic
poles and it is also surrounded by a magnetic
field.

• This magnetic field is what causes the needle of a
compass to point in different directions and the
poles of a magnet to point either north or south.
The earth is like a giant magnet!
The nickel iron core of the earth gives the earth a
magnetic field much like a bar magnet.
What are magnets used for?
&
Why do we need to
Do you like roller coasters or
other amusement park rides?
• If you answered yes, then you should know that a roller coaster
mainly uses magnets to achieve quick acceleration at the
beginning of the roller coaster ride. The type of magnets used
in a roller coaster may vary, but the roller coaster depends
upon both the negative and positive abilities of magnets.
Computers use magnets on all of
these parts:
Cooling fans
Floppy disk spinner
CD spinner
DVD spinner
Hard disk spinner
Never put a magnet near a
computer or it will cause the magnets
inside the computer to mess up.
Magnets are used in factories
• Magna-Rails
Positioned under conveyor belts, Magna-Rails hold parts firmly
to the belt even at high speeds and on up or down inclines as
steep as 90 degrees.

Places, such as car manufactures, also
use magnets to carry heavy metal from
place to place.
What else are magnets used for?
The Refrigerator
Uses magnets in its compressor
and ice maker dumper. It also
uses magnets in the strip
around the door to hold the
refrigerator door closed.

The clothes washer
Uses magnets in its pump and
agitator timer.

The clothes dryer
Uses magnets in its timer
and drum turner
What else uses magnets?
A CD spinner, DVD spinner, and head positioner all
uses magnets. A Television has lots of magnets in it
along with a stereo system and speakers. These all
work by using magnets.
Without magnets, you would not
be able to….
• Use the microwave
• Have a dishwasher
• Have a furnace
• Use a credit card
• Hear the phone ring
• Or hear the door bell ring
All of these things use magnets to work!
Cont.
Without magnets, you would not
be able to….
• Post up your sports schedules on the
refrigerator
• Turn on the ceiling fan
• Use the electrical can opener
• Ride in a moving cars
(that’s right, cars have LOTS of
magnets inside to make them work!)
Magnets are all around us. Chances
are, if something moves with electrical
power, then it has a magnet in it
somewhere. How do magnets work
you might want to know? That is what
you are going to begin to learn about in
our magnet unit.

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