State Lenz's law of electromagnetic induction:

Explanation

Lenz.s law determines the direction of induced current. According to this law, the induced.curreat produced in a circuit always flows in a direction that it opposes the change or cause which produces it. Lenz.s rule and law of conservation of energy Consider a solenoid connected to a galvanometer. Let a bar magnet with its north be moved towards the coil. Due to the movement of magnet, the magnetic flux linked with the coil changes and the induced current is produced. According to Lenz.s law, the . . direction of induced current opposes the cause, (motion of magnet). In order to oppose the cause, upper end becomes north pole. So to move the magnet towards coil, we have to work against force of repulsion. This mechanical work converts into electric energy. So Lenz.s law is in accordance with the law of conservation of energy.