JEE Main 2017 · 8 Apr · Shift 1 · Physics Q19

PhysicsSingle correct+4 / -1Question 19 of 90

A magnetic dipole in a constant magnetic field has :

maximum potential energy when the torque is maximum.

zero potential energy when the torque is minimum.

zero potential energy when the torque is maximum.

minimum potential energy when the torque is maximum.

Answer and worked solution

Official answer: C

$U=-mB\cos\theta$ and $\tau=mB\sin\theta$ . At $\theta=90^\circ$ the potential energy is zero and the torque is maximum.

JEE Main 2017 · 8 Apr · Shift 1, Physics question 19