Here are some things to do to finish this section.
What question did you think of that could be studied, or
observation could you make that is interesting or unexpected?
Send it to the Question board!
Discuss these questions with the people in your group. Please
send us a discussion of two of these
questions. Don't forget to tell us the group name.
(a)If we cut a long bar magnet in two, to make two shorter ones,
will the pieces want to stay together or fly apart?
(b)
If we break one of the flat black magnets as shown, will the pieces
want to stay together or fly apart?
You should be able to figure out these without actually breaking a
magnet. Of course, you should explain your reasoning, and discuss
the implications.
Give examples of how magnets are used around the house, at
school, in your car. Using your compass, try to determine where the
poles are for some of the magnets.
We have been
describing magnets and how they interact in terms of their poles.
However, there is another way to describe them, in which we draw
arrows on the sides of the magnet instead of poles on the ends
(these arrows have nothing to do with the magnetic field arrows
we were drawing earlier).
The arrows run around
the magnet, so that when you view the magnet from the N pole end,
they describe a counterclockwise path around the magnet.
Decorate some of your magnets with arrows like these, and then
observe how they account for the interaction of magnets, for the
various cases that the magnets are end-to-end or side-by-side: what
are the arrows doing when the magnets are attracting, and what are
they doing when the magnets are repelling? How could you use the
"arrow" description to explain the behavior of the broken magnet
shown above?
Hold a bar magnet so that the long axis is vertical, and touch a pair of paper clips to the bottom so that they hang down from it. What happens when you push the paper clips together? Why do they do this?
If there is something that you don't understand about magnets,
Ask us!
This is the end of this unit. (Check this
box ) The next section is about electromagnetism
We have been
describing magnets and how they interact in terms of their poles.
However, there is another way to describe them, in which we draw
arrows on the sides of the magnet instead of poles on the ends
(these arrows have nothing to do with the magnetic field arrows
we were drawing earlier).
The arrows run around
the magnet, so that when you view the magnet from the N pole end,
they describe a counterclockwise path around the magnet.
