A generator converts mechanical energy into electricity. The mechanical energy is supplied by a power plant as a mechanical energy, usually a gas or turbine engine that can be powered by gas, wind, steam or nuclear power. The power plant is used to turn a series of wire coils inside two magnetic fields. This creates an electrical charge, which is then distributed to a power source by an electrical circuit. The key point to note is that the generator itself does not make electricity. The electrical charge is already present in the wires. In a sense, the generator simply “gathers” the charge and sends it along the wire.

Here we have demonstrated a generator operated simply by moving the shaft of generator manually generating mechanical energy which is being converting into electricity indicated by LED which get turn on:

First step:  Disk is coupled with motor by the means of elastic rubber.

second step : LED get turn on when mechanical energy converts into electricity.

Generator and

Motor

A hand-cranked generator can be used to generate voltage to turn a motor. This is an example of energy conversion from mechanical to electrical energy and then back to mechanical energy.

As the motor is turning, it also acts as a generator and generates a “back emf”. By Lenz’s law, the emf generated by the motor coil will oppose the change that created it. If the motor is not driving a load, then the generated back emf will almost balance the input voltage and very little current will flow in the coil of the motor. But if the motor is driving a heavy load, the back emf will be less and more current will flow in the motor coil and that electric power being used is converted to the mechanical power to drive the load.

Lenz’s  law : A law of electromagnetism which states that, whenever there is an induced electromotive force (emf) in a conductor, it is always in such a direction that the current it would produce would oppose the change which causes the induced emf. If the change is the motion of a conductor through a magnetic field, the induced current must be in such a direction as to produce a force opposing the motion. If the change causing the emf is a change of flux threading a coil, the induced current must produce a flux in such a direction as to oppose the change.