State Lenz's law and prove that it is a specific representation of the law of conservation of energy.

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(N/A) Lenz's law states that the polarity of induced emf is such that it tends to produce a current which opposes the change in magnetic flux that produced it.
Proof of Conservation of Energy:
Consider a bar magnet being pushed towards a closed coil. As the North-pole of the magnet moves towards the coil,the magnetic flux through the coil increases. According to Lenz's law,the induced current in the coil will flow in a direction that creates a North-pole on the face of the coil towards the magnet. This creates a repulsive force between the magnet and the coil.
To continue moving the magnet towards the coil,we must do work against this repulsive force. This mechanical work done by the external agent is converted into electrical energy,which manifests as the induced current in the coil. If the current were to flow in the opposite direction (attracting the magnet),the magnet would accelerate towards the coil,increasing the flux and the current further,leading to an infinite increase in energy without any work done,which violates the law of conservation of energy. Thus,Lenz's law is a direct consequence of the law of conservation of energy.

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