Material: Collection of items in plastic bag, magnet.
1. Take each item out of the bag and see whether it is
attracted to the magnet. Separate the items into two piles of
items that do and do not attract the magnet.
2. Go around the room and touch at least ten different items
to see if they are magnetic. Do not touch any electrical outlets!
QUESTIONS/CONCLUSIONS
1. What is unique about each pile in 1)? Are there one or more
characteristics that are common to each of the two piles?
2. Are all the metals attracted to the magnet? If not, which
ones are and are not?
3. Of the items that are attracted to the magnet, which part
of the magnet seems to attract them the most?
4. Repeat some of the tests but do not actually touch the
item. For the magnetic ones, can you feel the attraction without
touching?
5. Discuss in your groups whether the magnetic items in the
room make sense.
1-2) Which Materials Does Magnetic
Attraction Pass Through?
Material: several size magnets, paper clips, plastic
cup, glass jar, paper, thin plywood, book, various metals,
ceramic.
1. Put each of the material above between the magnet and the
paper clips in turn. Move the magnet around and see if the paper
clips follow.
2. Put water in the drinking glass or pie plate. Place the
paper clips in the water and see if the magnets attract them?
QUESTIONS/CONCLUSIONS
1. Does the movement of the paper clips depend on the strength
of the magnet? Explain.
2. Can the paper clips be moved by acting through the book? By
the weak and strong magnets? Explain any difference.
3. Find out how many pages of the book each of the magnets
seems to be able to attract through.
4. Does the magnet act through the metals? Does it depend on
which kind of metal? How can you explain this?
5. Does the magnet act through the water?
1-5) Which End Of A Compass Is the North
Pole?
Material: compass, bar magnet.
This activity is a good one to do with the entire class.
Distribute a compass to each group. Ask them "Which end of the
compass is the north end or north pole?" "How can we find out?"
They should use the marked bar magnet to determine north and
south. Draw two diagrams: one with the north end of the bar magnet
near the compass and one with the south pole near the compass.
Make sure N and S is marked on the compass. Then draw a diagram of
the compass placed on earth with the north and south poles of the
Earth marked.
QUESTIONS/CONCLUSIONS
1. How can you determine experimentally which end of a compass
is actually north?
2. How could you find out which end of a compass is north if
you don't have another magnet?
3. Hang the bar magnet from a string. Which end points in the
north direction? Explain.
4. Which magnetic pole is located at the north end of the
Earth?
5. Why do we call the end of the compass that points in the
north direction the north pole?
1-6) Identifying the Poles of a Magnet
Material: compass, several shapes of magnets including
bar, cylinder, disk, magnet with unmarked poles (use small bar
magnets). Use as many different magnets as you can find.
The pointer of a magnet that points in the north direction is
actually a north pole of a magnet. Use this fact to determine
which part of all the magnets is a north and south pole. Determine
a way to find north and south for the disk.
QUESTIONS/CONCLUSIONS
1. How can you reconcile the fact that the north end of the
compass points towards the north pole of the earth? Don't north
and south poles attract?
2. Is it obvious which parts of the cylinder is north and
south? Explain.
3. Which parts of each of the magnets are north and south.
1-7) Floating Magnets
Material: Six (or more) small disc magnets with holes
in center, plastic tube, rubber stopper with one hole to fit tube.
Place a rubber stopper on the plastic tube about two inches
from the bottom (already done for you). Place the magnets with
holes on the tubes. Place them in different order so that they
attract and repel one another. First place the magnets so that
each magnet repels its adjacent ones. Hold the tube vertically and
observe. Then turn the tube horizontally and shake a little until
the magnets come to equilibrium. Observe what happens. You may
have to remove one or more magnets when the tube is held
horizontally.
QUESTIONS/CONCLUSIONS
1. When the magnets repel one another on the vertical plastic
tube, do the bottom magnets change position when new ones are
added to the top? Why?
2. Why are the magnets further apart on the top?
3. What is the position of the magnets when the tube is held
horizontally? Is this reasonable? Explain.
4. Where are the poles of the magnets located on the discs?
1-9) The Magic Dollar Bill
Material: A twenty dollar bill, a one dollar bill,
strong neodymium magnet, bar magnet. (Sorry, you will have to use
your own currency here!)
1. Take a one dollar bill and smooth it out. Place the bill
vertical and use a finger to hold it at the very top against the
edge of a table or chair. The bill should hang down freely and be
able to move. Touch a neodymium magnet to the dollar bill where it
is light in color. Pull the magnet away slowly and see if the
dollar bill is attracted and follows.
2. Now repeat the procedure with the twenty dollar bill but
bring the neodymium magnet to a place on the bill where it is
dark. Try to pull the bill out with the magnet.
3. Repeat the above procedure with the bar magnet.
QUESTIONS/CONCLUSIONS
1. Explain the difference. Why is it possible to move the
twenty dollar bill, but not the one dollar bill?
2. Why can the neodymium magnet attract the bill, but not the
bar magnet?
3. Lay the bills down on a wooden table and by moving both
magnets all around both bills, try to lift them?
1-10) The Mysterious Coins
Material: Several American and Canadian dimes, various
magnets including neodymium.
Place both coins on the table. Try to pick up both coins with
each magnet. Think about the differences. For the coins that are
attracted, see how many coins can be picked up with each magnet.
QUESTIONS/CONCLUSIONS
1. Explain the difference in behavior between the American and
Canadian dimes.
2. Explain the difference between using the various magnets,
especially the neodymium.
3. Do you predict that the American nickel will be magnetic?
Explain. Try it.
1-11) Which Part of a Bar Magnet
Attracts the Most?
Material: bar magnet, horseshoe magnet, disc magnet,
BBs, small paper clips, bowl slightly larger than bar magnet (use
pie dish or plastic storage container).
1. Place a bunch of paper clips in the bowl. Place the magnet
inside the bowl and pull it out while the magnet is holding lots
of paper clips. Where are the paper clips most strongly attracted?
2. Repeat experiment 1) using the BBs.
3. Predict what you think will happen if you repeat
experiments 1) and 2) using the horseshoe magnet and a disc
magnet. Then do the experiments.
QUESTION/CONCLUSIONS
1. Where are the paper clips most strongly attracted? the BBs?
Does this agree?
2. Where are the poles of a bar magnet?
3. Were you surprised by the results of using the horseshoe
and disc magnets? Why?
2-7) Telling Time With a Compass
Material: pencil, compass.
Take a compass outside on a sunny day. Stand holding the
compass facing north and align the compass needle along the N
direction on the compass. Place the pencil's eraser on the
compass's S with the pencil at a 450 angle to the horizontal
compass. The point of the pencil will be along N. Observe where
the shadow of the pencil falls on the compass. You can tell the
time by letting 3 o'clock being east, 6 o'clock being south, 9
o'clock being west and 12 noon being north. The time will be
standard time, not daylight savings time.
QUESTIONS/CONCLUSIONS
1. Does this technique sound like any other device you have
seen?
2. Why doesn't this technique work for daylight savings time?
Would it be worthwhile to design a device that would work for
daylight savings time?
2-8) Making a Nonmagnetic Compass
Material: Sharp stake, hammer, watch, large sheet of
paper.
Go outside on a sunny day and drive a stake into the ground,
but with it pointing straight up. Place a large sheet of paper
around the stake with the 12 hour marks on the circle drawn. Look
at the current time and rotate the sheet of paper until the shadow
of the stake points towards the current hour. Use standard time,
not daylight savings time. North will be halfway between the
shadow and the number 12.
QUESTIONS/CONCLUSIONS
1. Explain how the nonmagnetic compass and the previous
activity, Telling Time With a Compass, are consistent.
2. How can this device work for 12 noon?
3. When do we have to worry about the sun not producing a
shadow on our clock?
