Question

In a physics laboratory experiment, a coil with 200 turns enclosing an area of 12cm2 is rotated in 0.040 s from a position where its plane is perpendicular to the earth’s magnetic field to a position where its plane is parallel to the field. The earth’s magnetic field at the lab location is 6.0×10^−5T.

(a) What is the total magnetic flux through the coil before it is rotated? After it is rotated?
(b) What is the average emf induced in the coil?

Answer 1

given,

turns in coil (n) = 200 turns

area (A)= 12 cm²

time(t) = 0.040 s

electric magnetic field = 6 × 10⁻⁵ T

θ = 0°

a) total magnetic flux

∅ = n B A cos θ

∅ = 200 x 6 × 10⁻⁵ x 0.0012 x cos 0°

∅ = 1.44 × 10⁻⁵ Wb

b) average emf induced

`E = (d\phi )/(dt)`

`E = (1.44 * 10^(-6))/(0.040)`

`E = 3.6 mV`