Show that lenz law can be derived from the principle of conservation of energy?
Answers
LENZ'S LAW IN ACCORDANCE WITH THE LAW OF CONSERVATION OF ENERGY :
For example, in the experimental verification of Lenz's law, when N-pole of magnet is moved towards the coil, the upper face of coil acquires north polarity.
Therefore, work has to be done against the force of repulsion, in bringing the magnet closer to the coil.
Similarly, when N pole of magnet is moved away, south polarity develops on the upper face of the coil.
Therefore, work had to be done against the force of attraction, in taking the magnet away from the coil.
IT IS THE MECHANICAL WORK DONE IN MOVING THE MAGNET WITH RESPECT TO THE COIL THAT CHANGES INTO ELECTRICAL ENERGY PRODUCING INDUCED CURRENT.
THUS, ENERGY IS BEING TRANSFORMED ONLY.
When we do not move the magnet, work done is zero. Therefore, induced current is also not produced.
HENCE LENZ'S LAW OBEYS THE PRINCIPLE OF ENERGY CONSERVATION.
Conversely, Lenz's law can be treated as a consequence of the principle of energy conservation.
Explanation: