(a) State Lenz’s law.
(b) A rectangular coil of N turns is rotated with a constant angular speed about an axis through its centre in a uniform magnetic field. Using Lenz’s law, explain why the direction of the induced current in the coil reverses after every half-turn.
(c) During one complete revolution, how does the magnitude of the induced emf vary with time? Describe the qualitative shape of its time variation and explain how its maximum value depends on the coil parameters N, A, B and the angular speed of rotation.