The priciple of electric generator is based on the eletromagnetic induction when number of magnetic line are change in the loop produces the emf and induced current in the loop

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Principle:\xa0An electric generator works on the principle of electromagnetic induction. When a coil is rotated between the magnet or when the magnet is rotated in and out of the coil the current is induced in the coil and the direction of current is given by Fleming’s right hand rule.