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Question
Answer the following question in brief.
What happens if a bar magnet is cut into two pieces transverse to its length/along its length?
Solution
- When a magnet is cut into two pieces, then each piece behaves like an independent magnet.
- When a bar magnet is cut transverse to its length, the two pieces generated will behave as independent magnets of reduced magnetic length. However, the pole strength of all the four poles formed will be the same as that of the original bar magnet. Thus, the new dipole moment of the smaller magnets will be,
`therefore m = m xx 2l`
`vec("m"_1)="q"_"m"(vec("l"_1))`, `vec("m"_2)="q"_"m"(vec("l"_2))`
- When the bar magnet is cut along its length, the two pieces generated will behave like an independent magnet with reduced pole strength. However, the magnetic length of both the new magnets will be the same as that of the original bar magnet. Thus, the new dipole moment of the smaller magnets will be
`vec("m"_1)=("q"_"m")_1(2vec("l"))`, `vec("m"_2)=("q"_"m")_2(2vec("l"))`
Pole strength is directly proportional to cross-section area.
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