An industrial park is to be supplied with electrical energy from a remote power station. To transmit power over long distances with minimal energy loss, transformers are used to change the voltage. Which type of current must be used to operate these transformers, and what level of voltage should be used in the long-distance transmission lines?
Alternating current (a.c.) and high voltage
Alternating current (a.c.) and low voltage
Direct current (d.c.) and high voltage
Direct current (d.c.) and low voltage
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.