Question

Lenz's law is in accordance with the law of conservation of
A: electric current
B: energy
C: electromotive force
D: electric charge

Answer 1

When we move the N-pole of the magnet towards a coil, its upper face gets north polarity. Hence, work is to be done against the repulsive force.When the N pole is moved away from the coil, the upper face develops south polarity. Therefore, work had to be done against the attractive force.

Complete step by step answer:
Lenz law states that when magnetic flux is increased through a closed loop, a current is induced which opposes the rate of change of flux or the cause that produces it.The work that is required to move the magnet will induce an electrical energy within it and the energy generates current. It is a clear condition of the transformation of energy.When the magnet is stationary, it does not produce any current as there is zero work done there.From this we understand that energy is preserved by getting converted from one form to another. This means that Lenz’s law is in accordance with law of conservation of energy.

Hence, option B is the correct answer among the given four options.

Note: When the direction of the magnetic field that forms the current is in the same direction as that of the induced current, the two fields would get added up and generate a current with twice the magnitude. This creates a larger magnetic field, which will generate more current. When this process continues, Lenz's law is violated.