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?