Question

Identify the expression for the motional electromotive force from the following?

(a) E = -vLB

(b) E = vLB

(c) E = \(\frac {v}{LB}\)

(d) E = \(\frac {LB}{v}\)

This question was addressed to me during an online exam.

I need to ask this question from Electromagnetic Induction in section Electromagnetic Induction of Physics – Class 12

Answer 1

The correct option is (a) E = -vLB

The best I can explain: Motional electromotive is the emf induced by the motion of the conductor across the magnetic field. The expression for motional electromotive force is given by:

E = -vLB

This equation is true as long as the velocity, magnetic field, and length are mutually perpendicular to each other. The negative sign is associated with Lenz’s law.