Question

The time period of oscillation of a magnet in a vibration magnetometer is 1.5 sec. The time period of oscillation of another magnet similar in size, shape and mass but having 1/4 magnetic moment than that of the 1st magnet oscillating at the same place will be

• A. 0.75 sec
• B. 1.5 sec
• C. 3.0 sec
• D. 6.0 sec

Answer 1

Answer: (C)

3.0 sec

Answer 2

$\frac{T_{2}}{T_{1}}=\sqrt{\frac{M_{1}}{M_{2}}}=\sqrt{\frac{M_{1}}{\frac{1}{4}M_{1}}}=2$ $\therefore\,T_{2} = 2T_{1} = 3 s$