A straight copper wire is moved through a uniform magnetic field, cutting the magnetic field lines at a right angle. This induces an electromotive force (e.m.f.) across the ends of the wire.
Which of the following changes would increase the magnitude of the induced e.m.f.?
Moving the wire more slowly through the magnetic field
Using a stronger magnet to increase the magnetic flux density
Replacing the copper wire with a thicker copper wire of the same length
Moving the wire parallel to the direction of the magnetic field lines
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.