Physics for IGCSE & O level - Magnets And Currents (Section 4 - No. 19)
What do the brushes in an electric motor or generator do?
They provide the magnetic field.
They make contact with the rotating parts to conduct current.
They increase the voltage output.
They convert AC to DC.
Explanation
Brushes maintain contact with the rotating commutator or slip rings to allow the current to flow to and from the external circuit.