A vertical wire passes through a horizontal card. An electric current flows upwards through the wire, towards an observer looking down from above.
Describe the pattern and direction of the magnetic field lines due to this current as viewed from above the card.
A straight current-carrying wire is placed in a horizontal magnetic field between two magnetic poles, with the North pole on the right and the South pole on the left. The current flows directly into the page, which causes a downward magnetic force to act on the wire.
State two different ways to increase the magnitude of the magnetic force on the wire.
A straight current-carrying wire is placed in a horizontal magnetic field between two magnetic poles, with the North pole on the right and the South pole on the left. The current flows directly into the page, which causes a downward magnetic force to act on the wire.
State two different ways to make the magnetic force on the wire act upwards.
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.