A circular loop of area $0.02\, m^2$ carrying a current of 5 A is held with its plane normal to a magnetic field of 0.2 T. The torque acting on the loop is

0

The correct answer is Option (4) → 0

Torque on a current loop is:

$\tau = N I A B \sin \theta$

Here, the plane of the loop is normal to the magnetic field, which means the area vector is parallel to the magnetic field.

Thus, $\theta = 0^\circ \Rightarrow \sin \theta = 0$

$\tau = N I A B \sin 0 = 0$

Torque τ = 0