Two opposite sides of a rectangular motor coil are perpendicular to the same uniform magnetic field. Why do these sides experience forces in opposite directions?
The magnetic fields at the two sides point in opposite directions.
The magnetic flux densities at the two sides have different values.
The resistances of the two sides have different values.
The currents in the two sides flow in opposite directions.
86 exam-style questions on Edexcel GCSE Physics 12.3 The motor effect, covering 12.3.1 The motor effect, 12.3.2 Fleming's left-hand rule, 12.3.3 Force on a conductor, and 12.3.4 Electric motors. Each one has a worked solution and a mark scheme showing where the marks go.