As a result of change in the magnetic flux linked with the closed loop shown in the figure, an emf of V volt is induced in the loop. The work done (in joule) in taking a charge Q coulomb once along the loop is:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → QV
The induced emf of a loop is defined as the work done per unit charge in taking a charge once round the loop. For an emf of V volt, the work done on a charge Q taken once round the closed loop is
\( W = Q\times\varepsilon = QV \)
NCERT (2026-27):
Displacement Current – “… Faraday’s law of induction states that there is an induced emf equal to the rate of change of magnetic flux. Now, since the emf between two points 1 and 2 is the work done per unit charge in taking it from 1 to 2, the existence of an emf implies the existence of an electric field.”