The commutator in an electric motor is used to:

Correct option is D

Correct Answer:(D) reverse the direction of current flowing through the coil

Explanation:

• In an electric motor, the commutator is a device that reverses the direction of current flowing through the coil every half turn, ensuring that the coil continues to rotate in the same direction.
• This reversal of current ensures that the force acting on the coil keeps the motor turning in the same direction, instead of stopping or reversing.

Why the other options are incorrect:

• change the direction of the magnetic field: The commutator does not change the magnetic field; it only reverses the direction of the current flowing through the coil.
• maintain the magnetic field in the circuit: The magnetic field is generated by the permanent magnets or electromagnets, not by the commutator.
• maintain the potential difference in the circuit: The commutator doesn't maintain potential difference; it only ensures continuous rotation by reversing the current in the coil.