An industrial neon sign requires a supply voltage of 15 kV15\text{ kV}15 kV. The mains electricity supply is 240 V. A transformer is used to supply the correct voltage to the neon sign. There are 80 turns on the primary coil of the transformer.
Calculate the number of turns on the secondary coil.
Draw a labelled diagram of a step-up transformer. On the labels, state a suitable material for each of the major components.
Explain how a transformer transfers electrical energy from the primary coil to the secondary coil without any direct electrical connection between them.
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.