Question

As a new electrical engineer for the local power company, you are assigned the project of designing a generator of sinusoidal ac voltage with a maximum voltage of 120 V. Besides plenty of wire, you have two strong magnets that can produce a constant uniform magnetic field of 1.5 T over a square area with a length of 10.2 cm on a side when the magnets are separated by a distance of 12.8 cm . The basic design should consist of a square coil turning in the uniform magnetic field. To have an acceptable coil resistance, the coil can have at most 400 loops.

What is the minimum rotation rate of the coil so it will produce the required voltage? Express your answer using two significant figures.

Answer 1

The rotation rate is 15.3 rad/s.

Step-by-step explanation:

maximum voltage, V = 120 V

Magnetic field, B = 1.5 T

length, L = 10.2 cm

width, W = 12.8 cm

Number of loops, N = 400

Let the rate of rotation is w.

The maximum voltage is given by

V = N B A w

120 = 400 x 1.5 x 0.102 x 0.128 x w

w = 15.3 rad/s