Thames & Kosmos Electricity and Magnetism 620417, Руководство по эксперименту

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EXPERIMENT 40
Magnetism
41
1
2
3
Magnetic force
made visible
It’s kind of a shame that you can’t see
magnetic forces. But there’s a trick for
making them visible — by using the iron
powder from the plastic box.
HERE’S HOW
Place the two touching bar magnets flat
on the table. Spread out the iron powder
fairly evenly in the box and hold the box a
few millimeters above the magnets
(which creates clearer patterns than
when you hold the magnet directly
against the box).
Tap gently on the box. The iron particles
will form a picture, as if painted by the
hand of a ghost (figure 1).
You might have to perform this experi-
ment a few times before you get the hang
of making a really nice-looking pattern.
Stand the bar magnet upright (figure 2)
and repeat the experiment. How does the
picture look now?
Also try seeing what kinds of patterns the
ring magnet makes (figure 3).
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