An offshore wind farm is located far from a coastal town where the generated electricity is consumed. To transmit this electrical energy efficiently over long distances, which combination of current type and voltage adjustment must be used at the wind farm before transmission?
Alternating current (a.c.), stepped up to a high voltage
Alternating current (a.c.), stepped down to a low voltage
Direct current (d.c.), stepped up to a high voltage
Direct current (d.c.), stepped down to a 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.