Bar Magnet and Compass Interactive
The black rectangle represents a bar magnet.
The magnet's North and South
poles are labeled. The other item represents a compass; the red end
of the needle is the end that would point towards Earth's North Magnetic Pole. Notice that the red end of the compass needle points toward the south pole of the magnet. For historical reasons, what we call "Earth's North Magnetic Pole" is actually the south pole of Earth's magnetic field! Yikes!
Drag either the compass or the magnet around to explore the magnetic
field around the bar
magnet. Can you determine the shape of
the magnetic field?
(Note: If you cannot see the animation below, or it is not working properly,
you may need to download the latest Flash
This is an early draft version of this activity. We expect to replace it with
a better version soon. Some things to be aware of:
- If you drag either the compass or the magnet off screen and let go, you
won't have any way to get them back. Reload/refresh the web page to start
- The behavior of the compass might be a bit different in the real world
when you place it on top of the magnet.
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