A bar magnet is dropped vertically through a solenoid (coil of wire). As the magnet falls through the solenoid, an electromotive force (e.m.f.) is induced across the ends of the coil.
Which change would increase the peak magnitude of the induced e.m.f.?
dropping the magnet from a lower height above the solenoid
using a solenoid with thicker wire but the same number of turns
dropping the magnet from a greater height above the solenoid
reversing the polarity of the magnet before dropping it
275 exam-style questions on CIE IGCSE Physics 4.5 Electromagnetic effects, covering 4.5.1a Electromagnetic induction, 4.5.1b Direction of an induced e.m.f., 4.5.2 The a.c. generator, 4.5.3a Magnetic effect of a current and its applications, 4.5.3b Strength and direction of the field around wires and solenoids, 4.5.4a Force on a current-carrying conductor, 4.5.4b Force on beams of charged particles, 4.5.5 The d.c. motor, 4.5.6a Construction and operation of a transformer, 4.5.6b Turns ratio and current in a transformer, and 4.5.6c High-voltage transmission of electricity. Each one has a worked solution and a mark scheme showing where the marks go.