Question

Why are carbon brushes used? How does this work? In order to find answers to such questions, visit a nearby workshop and try to understand the construction of an electric motor.

Answer 1

Hint:Electric motor is an electrical device to convert electrical energy into mechanical energy. Electric motors generate force in the torque through the interaction between the motors’ magnetic field and the electric circuits in the wire winding. Now, to know the use of carbon brushes step to the complete solution.

Complete answer:
Electric motors have three main components:
-Armature
-Brushes
-Split rings
Armature is the major component which hosts the winding of the motor. The magnetic field is generated by the electromagnets and the armature windings interact with the magnetic field. The electric current on interaction with the magnetic field creates force which in turn creates torque.

Brushes are used to serve electrical contact between the stationary points and the moving surfaces. They are mainly used to transfer power from rotatory armature coils to stationary wires. They are used to reduce the damage of the motors.Split rings are used to supply unidirectional current to rotor coils to generate torque in the same direction.

Note:There is a drawback of the brushes that for every rotation of armature coil brush rub against the commuter, friction causes wear and tear of the brush and commuterHence, brushless motors are used.Carbon brushes work as a lubricant for the motors.