1. A circular coil of wire with 10 turns and a 4.0 cm radius is located between the poles of a large electromagnet that produces a uniform magnetic field of 0.5T. The surface of the loop, which is origianlly parallel to the field, is rotated in 0.1 s so that its surface is perpendicular to the field. Calculate the average induced emg across the ends of the loop as the coil rotates.
2. An airplane with a wingspan of 50m flies horizontal to the earth at a location where the downward component of the earth's magnetic field is 0.6*10^-4 T. Find the difference in potential between the tips of the wing when the velocity of the plane is 250 m/s.