Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): A closed loop is held at rest between the poles of two strong permanent magnets. The magnets are fixed in place. No current is induced in the loop.
Reason (R): The magnitude of the induced emf in a circuit is equal to the magnetic flux through the circuit.
In the light of the above statements, choose the most appropriate answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → (A) is correct but (R) is not correct.
Assertion (A) A closed loop is held at rest between the poles of two strong permanent magnets. The magnets are fixed in place. No current is induced in the loop. — True. The loop and the magnets are all at rest, so the flux through the loop stays the same. A strong magnet gives a large flux, but a flux that does not change induces no current.
Reason (R) The magnitude of the induced emf in a circuit is equal to the magnetic flux through the circuit. — False. By Faraday’s law, the emf depends on how fast the flux changes. A large steady flux gives no emf at all.
NCERT (2026-27):
Lenz’s Law and Conservation of Energy – “… However strong the magnet may be, current can be induced only by changing the magnetic flux through the loop.”
Faraday’s Law of Induction – “The magnitude of the induced emf in a circuit is equal to the time rate of change of magnetic flux through the circuit.”