Question

A circular loop of wire is carrying a current i ( as shown in the figure). On applying a uniform magnetic field inward perpendicular to the plane of the loop:

• A. Contract
• B. Expand
• C. Move along the positive x-direction
• D. Move along the negative x-direction

Answer 1

The correct option is B Expand

As the direction of current inoop is clockwise,

When magnetic filed is applied inside the plane of paper.

Taking a element dl in the direction of current I,

The force experienced by dl is in direction of $(dl\times B)$

The direction of force is away from the centre of the loop,

And the force will try to expand the loop.

Hence Option $\text{B}$ is the correct answer.