Question

A coil of wire with 60 turns lies on the plane of the page, and a uniform magnetic field points into the page with a strength of 1.30 T. The coil has an initial area of 0.790 m2 and is then elongated so that its area decreases to 0.370 m2 in 0.80 s. What is the magnitude of the average induced emf in the coil while its area is changing

Answer 1

Answer: -40.95volts

Explanation:

The emf induced when the area of a coil changes in a magnetic field is given by:

E = -NB(∆A/∆t)

B =1.30T, N=60 turns,

∆A =0.790- 0.370 = 0.42

∆t = 0.8s

E = - 1.3 ×60 × (0.42/0.8)

E = - 40.95volts