An engineer is testing a sensor that detects the motion of a magnet relative to a stationary coil of wire. Under which of the following conditions will the magnitude of the induced electromotive force (emf) across the coil be the greatest?
The magnet is held at rest inside the coil.
The magnet is moved slowly through the coil.
The magnet is moved rapidly through the coil.
The magnet is held at rest outside the coil.
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.