Question

Current $i$ is flowing in each of the two similar coaxial circular coils in the same direction. If the loops are moved towards each other, the following phenomenon will happen :

• A. current in each loop will remain same
• B. current in each loop will increase
• C. current in each loop will decrease
• D. current in one loop will increase and that in another loop will decrease

Answer 1

Answer: (C)

current in each loop will decrease

When the coils approach each other, the flux linked with each coil will increase. So, in accordance with Lenz's law, current will be induced in each coil which will try to decrease the flux i.e the induced current in each coil will be opposite to the initial current. Hence, the current in each coil will decrease as they approach each other.