Question

An isolated inner coil $\text{A}$ is placed concentrically inside an outer coil $\text{B}$ as shown in the figure. What will be the direction of current in the coil $\text{A}$, as the switch $\text{S}$ is closed ?

• A. Clockwise
• B. Anticlockwise
• C. first anticlockwise and then clockwise
• D. first clockwise and then anticlockwise

Answer 1

The correct option is A Clockwise

When the switch $\text{S}$ is closed, the current will flow in anticlockwise direction in coil $\text{B}$.

This current will generate a magnetic field inside the coil $\text{B}$ in the direction perpendicular to the plane of coil and directed outwards.

Due to this magnetic field, a current is induced in the coil $\text{A}$, such that it opposes the increment of outward magnetic flux through the coil.

Therefore, the current will flow in the clockwise direction in the coil $\text{A}$.

Hence, option $\left(A\right)$ is the correct answer.