Question

A magnetic needle suspended by a silk thread is vibrating in the earth's magnetic field. If temperature of the needle is increased to ${1000}^{0}C$, then

• A. The time period decreases
• B. The time period remains unchanged
• C. The time period increases
• D. The needle stops vibrating

Answer 1

The correct option is C The time period increases

Time period T is directly proportional to the inverse of the root of magnetic moment M as

$T\propto \frac{1}{\sqrt{M}}$

Since magnetic moment decreases with increase in temperature so the time period will increase.