A straight wire carrying an electric current is positioned perpendicular to a magnetic field, resulting in an electromagnetic force acting on the wire.
Which statement is correct?
The force acts in a direction parallel to the magnetic field lines.
Reversing only the direction of the magnetic field reverses the direction of the force.
Reversing both the current and the magnetic field reverses the direction of the force.
The wire must be made of a magnetic material, such as iron, for a force to exist.
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.