As electric generatar produce electric current due to magnetic induction than why current don't produce in electric motor as magnetic induction should also occur in electric motor?

Answer 1

I will attempt to answer the question I think your asking: 'If an electric generator produces an electric current due to magnetic induction, then why isn't a current produced via the same mechanism in an electric motor?' The answer to the best of my understanding is that it is, or at least, it would be. The reason is that in a generator a conducting wire is rotated in a magnetic field and this induces a current as each charged particle experiences a force as determined by F=q(vxB) [this is the vector form of the equation using the vector product] or F=Bqv if you are unfamiliar with vectors. As this causes electrons to move this manifests itself as an alternating current in a wire. Conversely in a motor and alternating current is passed through a magnetic field in a coil of wire, this time the wire now experiences a force F determined by F=I(lxB). This produces a torque on the centre of the motor and it is this torque that drives the motor. However if you were to rotate the coil of the motor externally without supplying a current to it then the reverse process would take place. This would induce an AC current in the motor which would now function as a generator. As a aside if this current was then driven through the generator it would then rotate exactly as the motor did.