Question

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

Answer 1

Answer: (C)

The time period increases

Answer 2

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