In a simple direct-current (DC) motor, a split-ring commutator is used. Which statement correctly describes how the split-ring commutator enables the coil to rotate continuously in one direction?
It reverses the direction of the magnetic field every half turn of the coil.
It reverses the direction of the current in the coil every half turn of the coil.
It maintains a constant current direction relative to the coil at all times.
It increases the voltage supplied to the coil as it passes the horizontal position.
31 exam-style questions on CIE IGCSE Physics 4.5.5 The d.c. motor. Each one has a worked solution and a mark scheme showing where the marks go.