The brushes are used to transfer electrical power between ______________.

The brushes in an electric motor or generator play a crucial role in the function of the device by transferring electrical current. They make contact with the commutator, which is attached to the armature winding. As the armature spins, the brushes touch the commutator segments, allowing for a continuous transfer of electrical power between the moving armature and the stationary external circuit.

In the context of the options provided, focusing on the field coils and the armature clarifies that while brushes directly contact the commutator, their primary purpose is indeed to facilitate the flow of electricity to and from the armature, while ensuring that the magnetic fields created in the field coils interact effectively for proper operation.

Understanding how electrical current is managed through the brushes, commutator, and armature gives insight into the overall functioning of motors and generators in automotive applications. This knowledge is vital for diagnosing issues related to power transfer and ensuring efficient operation of the electrical systems in vehicles.