Describe the working principle of direct current motor.
Describe the factors that affect the speed of rotation of an electric motor.
State that a current-carrying coil in a magnetic field experiences a turning effect and that the effect is increased by:
– increasing the number of turns on the coil
– increasing the current
– increasing the strength of the magnetic field
Relate this turning effect to the action of an electric motor including the action of a split-ring commutator.