Question

A current carrying loop is placed in a uniform magnetic field. The torque acting on it does depend upon

• A. shape of the loop keeping perimeter fix
• B. area of the loop
• C. value of the current
• D. magnetic field

Answer 1

Answer: (A), (B), (C), (D)

The correct options are
A area of the loop
B shape of the loop keeping perimeter fix
C value of the current
D magnetic field

Torque $\overrightarrow{\tau }=\overrightarrow{\mu }\times \overrightarrow{B}$ where $\overrightarrow{\mu }=iA\hat{n}$
$i$ is the current in the loop and $A$ is the area of the loop. $\hat{n}$ is a unit vector perpendicular to the plane of the loop.
Area will depend on the shape. Hence, $\overrightarrow{\tau }$ will depend on area, current and magnetic field.