Commutators are used in DC machinery, such as universal motors and DC generators. A motor's windings get an electric current from a commutator. By reversing the direction of the current in the spinning windings every half turn, a constant rotational torque is generated.
According to this option b) is correct.
Describe a DC machine.
An electro-mechanical energy conversion system is known as a DC machine. There are two different kinds of DC machines: a DC motor and a DC generator. A DC motor transforms D.C. electrical power into mechanical power (ωT), whereas a DC generator converts mechanical power (T) into DC electrical power (EI).
What does a DC machine do?
An electrical device called a DC generator's principal job is to turn mechanical energy into electricity. Based on the electromagnetic induction theory of Faraday's Laws, an emf will be produced when the conductor cuts the magnetic flux.
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