Question

There is a uniform magnetic field directed perpendicular and into the plane of the paper. An irregular-shaped conducting loop is slowly changing into a circular loop in the plane of the paper. Then

• A. Current is induced in the loop in the anticlockwise direction
• B. Current is induced in the loop in the clockwise direction
• C. AC is induced in the loop
• D. NO current is induced in the loop

Answer 1

The correct option is A

Current is induced in the loop in the anticlockwise direction

Explanation for the correct option:

In the case of option A,

1. The magnetic flux associated with the conducting loop grows as it gradually transforms into a circular loop in the plane of the paper.
2. Thus, the current in the loop is created in a way that opposes the growth in flux.
3. As a result, the induced current moves counterclockwise.

Explanation for the incorrect options:

In the case of option B,

1. The direction of flux is clockwise and the current opposes the flux so it can't be induced in the clockwise direction.

In the case of option C,

1. There is no evidence that AC is induced while changing shape. However, the magnetic flux increase because of changes in the shape.

In the case of option D,

1. The current induced in the loop follows the direction which is opposite to the direction of flux. So, this option is inappropriate.

Hence, option A is the correct answer.