What is the peak emf generated (in v) by rotating a 1000 turn, 42.0 cm diameter coil in the earth's 5.00 ✕ 10−5 t magnetic field, given the plane of the coil is originally perpendicular to the earth's field and is rotated to be parallel to the field in 12.0 ms?

5.77 Volt

Explanation:

N = 1000, Diameter = 42 cm = 0.42 m,  t = 12 ms = 12 x 10^-3 s

Change in magnetic field, B = 5 x 10^-5 T

The peak value of emf is given by

e = N x dФ / dt

e = N x A x dB/dt

e = (1000 x 3.14 x 0.21 x 0.21 x 5 x 10^-5) / (1.2 x 10^-3)

e = 5.77 Volt

answer; equivalent to a one(1) horsepower motor;