Question

A circular coil is placed near a current-carrying conductor, both lying on the plane of the paper. The current is flowing through the conductor in such a way that the induced current in the loop is clockwise as shown in the figure. The current in the wire

 

• A. time-dependent and downward
• B. steady and upward
• C. time-dependent and upward
• D. An alternating current

Answer 1

The Correct Option is A

To analyze the given problem, we use Faraday's Law of Induction and Lenz's Law. The setup involves a circular coil placed near a current-carrying conductor, both lying on the plane of the paper. The induced current in the loop is clockwise.

Analyzing the Induced Current 

1. Direction of the Induced Current:
   The induced current is clockwise. By Lenz's Law, it must oppose the change in magnetic flux.
2. Change in Magnetic Flux:
   A clockwise induced current means the magnetic flux through the loop is increasing out of the plane. To oppose this, the induced magnetic field is into the plane.
3. Current in the Wire:
   For the magnetic flux to be increasing out of the plane, the magnetic field at the loop’s location must be increasing and directed out of the plane. According to the right-hand rule, this happens if the current in the wire is downward.
4. Time Dependence:
   Since the flux is changing, the current in the wire must be increasing with time — i.e., time-dependent.

Conclusion

The current in the wire is time-dependent and downward.

Final Answer: (A): time-dependent and downward

Answer 2

In this scenario, the loop is positioned to the right of the current-carrying wire, even though it might seem as if it's on the left side. This is because, when you move in the direction of the current, the loop is situated to the right.

Now, as the current diminishes, the induced current within the loop is in a clockwise direction (S), as illustrated in the diagram.

Correct Option: (A): time-dependent and downward