A transformer has 300 turns on its primary coil and 9000 turns on its secondary coil. Connected in this way, for what purpose could this transformer be used?
to convert the 4000 V4000\text{ V}4000 V a.c. output of a generator to 120 000 V120\,000\text{ V}120000 V for long-distance power transmission
to convert the 120 000 V120\,000\text{ V}120000 V d.c. supply from a power line to 4000 V4000\text{ V}4000 V for local transmission
to use a 240 V240\text{ V}240 V a.c. mains supply to operate an 8 V8\text{ V}8 V motor
to use an 8 V8\text{ V}8 V d.c. supply to operate a 240 V240\text{ V}240 V lamp
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.