The magnetic flux linked with a coil (in Wb) is given by the equation $\phi=5t^2+3t+16$. The magnitude of induced emf in the coil at the fourth second will be

A 10 V

B 33 V

C 43 V

D 108 V

The answer is C.

Solution

$e=-\dfrac{d\phi}{dt}=-(10t+3)$. At $t=4$ s, $|e|=10\times4+3=43$ V.

Concept Faraday's law of electromagnetic induction

40 questions from this chapter have appeared across 23 exam years.