Principle :

    A.C. generators or alternators (as they are usually called) operate on the same fundamental principles of electromagnetic induction as D.C. generators.

    Alternating voltage may be generated by rotating a coil in the magnetic field or by rotating a magnetic field within a stationary coil. The value of the voltage generated depends on-

                     the number of turns in the coil.

                     strength of the field.

                     the speed at which the coil or magnetic field rotates.   

 

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     Working of Alternator