→
WHAT’S HAPPENING?
HERE'S HOW
1. Place the needle against the compass.
2. Do the same with the iron rod.
3. Now stroke the iron rod 50 to 70 times
across one of the large surfaces of the
block magnet.
Important! Always stroke in the same
direction across the same surface of the
magnet.
4. Now move the block magnet far away
and move the iron rod close to the
compass needle again.
5. Now, stroke the sewing needle across
the block magnet as you did in step 3,
and look what happens when you hold
the needle close to the compass.
Keep the magnetized needle in a safe
place — you’ll need it again later.
A new magnet
is born
YOU WILL NEED
→ block magnet
→ iron rod
→ compass
→
long sewing needle
Without the “treatmen
t” with the block
magnet, the compass n
eedle won’t react
much to either the iron r
od or the sewing
needle (if it does, the s
ewing needle
must already have had c
ontact with a
magnet). With the iron r
od, still nothing
happens after “treatm
ent” with the
magnet. The sewing ne
edle, on the other
hand, astonishingly ret
ains its magnetic
force — the compass n
eedle reacts
strongly to it. That is d
ue to the fact that
sewing needles are ma
de of steel. Steel
has the property of rem
aining magnetic
after being stroked wit
h a magnet.
1
2
4
5
3
Magnets, Iron, and Poles |
9
EXPERIMENT 6
Summary of Contents for 665050
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