Question

The time period of vibration of magnetic dipole is $T$. On bringing a bar magnet closer along the axis of vibration, the new time period $T^{\prime }$ will be

• A. $T^{\prime }>T$
• B. $T^{\prime }<T$
• C. $T^{\prime }=T$
• D. none of these

Answer 1

The correct option is B $T^{\prime }<T$

When we bring a bar magnet near a magnetic dipole placed in magnetic field then it will tend to reduce the restoring torque acting on the dipole while doing SHM.

Therefore, when restoring torque is lesser then the new time period $T^{\prime }$ will be lesser than the previous time period $T$.