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Assertion (A): A conducting ring is placed in the plane of a circuit (as shown in a figure). When the resistance of a rheostat in the circuit is decreased, the current induced in the ring is clockwise. Reason (R): The magnetic flux through the ring is directed into the page and is increasing.

1. (A) is true, (R) is true, and (R) is the correct explanation of (A).
2. (A) is true, (R) is true, but (R) is NOT the correct explanation of (A).
3. (A) is true, (R) is false.
4. (A) is false, (R) is true.

Correct answer: (A) is false, (R) is true.

Solution

When rheostat resistance decreases, main circuit current increases, so magnetic flux through the ring (into the page) increases. By Lenz's law, the induced current must oppose this increase, so it creates flux out of the page inside the ring, which corresponds to an anticlockwise induced current (when viewed from the front/west). The assertion that the induced current is clockwise is therefore false. The reason correctly describes the flux situation. Hence (A) is false and (R) is true.

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