equation is called Faraday’s law of induction where Φ (phi) is the flux linked with coil. Let Φ0 be the flux linked with single turn. If there are N turns in the coil, the flux linked with the coil is N Φ0

So far we have not specified the direction of the induced EMF or induced current. In the previous example, we have observed that an induced current is set up in the loop.

• What is its direction?
  
• Can you apply conservation of energy for electromagnetic induction?

Lenze Law

When we push the bar magnet towards the coils, current is generated, in other word electromagnetic induction takes place and mechanical energy is converted into electrical energy.

Let us discuss it in detail.
We know that when a bar magnet is pushed towards a coil with its north pole facing the coil an induced current is set up in the coil. Let the direction of current in the coil be in clockwise direction with respect to north pole of the bar magnet. Then this current carrying loop behaves like a magnet, with its south pole facing the north pole of bar magnet. In such a case, the bar magnet attracts the coil. Then it gains kinetic energy. This is contradictory to conservation of energy. So our assumed clockwise direction of induced current is wrong. Hence the correct direction of induced current has to be in anticlockwise direction with respect to north pole of the bar magnet. In such a case, the north pole of the coil faces the north pole of the bar magnet as shown in figure 15. Then north pole of bar magnet is repelled by the north pole of the coil. Hence we need to do work to overcome this force. This work done on the magnet is converted into electrical energy in the coil. In this way conservation of energy takes place in electromagnetic induction.

Let us see a case where the bar magnet is pulled away from the coil, with north pole facing the coil. In such case, the coil opposes the motion of bar magnet to balance the conversion of mechanical energy into electric