A magnetic needle suspended by a silk thread is vibrating in the earth's magnetic field. If the temperature of the needle is increased by 500°C, then

(a) The time period decreases

(b) The time period remains unchanged

(c) The time period increases

(d) The needle stops vibrating

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Concept Questions :-

Bar magnet

$T\propto \frac{1}{\sqrt{M}}$. Since magnetic moment decreases with increase in temperature hence time period T increases.

Difficulty Level:

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