Question

Vibration magnetometer works on the principle of

• A. torque acting on the bar magnet and rotational inertia
• B. force acting on the bar magnet and rotational inertia
• C. both the force and torque acting on the bar magnet
• D. neither force nor torque

Answer 1

The correct option is A torque acting on the bar magnet and rotational inertia

When the bar magnet in the deflection magnetometer is displaced , a torque acts on it due to the horizontal earth's magnetic filed. So the magnet vibrates and alligns parallel to the earth's magnetic field.