This law states that the direction of induced e.m.f. is such that the current product by it sets up a magnetic field opposing the motion or change producing it.

The statement will be clarified from the following experiment.
When the bar magnet is moved towards the coil, as shown in an e.m.f. is induced in the coil, which cause an electric current to flow through the coil in the direction shown in . Due to flow of this electric current through the coil magnetic field is produced, north pole adjacent to north pole of the bar magnet and south pole on other end, which can be determined from helix rule explained in. Now since similar poles repel each other, therefore, the movement of the bar magnet towards the coil is opposed by the field produced. Mechanical energy is expended in moving the bar magnet towards the coil against the force of repulsion and this expended energy is converted into electrical energy.

The same results will be observed when the bar magnet is moved away from the coil.

When the bar magnet is moved away from the coil, an e.m.f. is induced in the coil, current flows through it in the direction opposite to that in which it was flowing when the magnet was moved towards the coil, so magnetic field will be produced of opposite polarity i.e. south pole adjacent to north pole of the bar magnet. Therefore, force f attraction will be exerted between the coil and bar magnet, which will oppose the movement of the bar magnet away from the coil. Mechanical energy is expended in this case also and is converted into electrical energy.

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