Answer:
Lenz's law
Step-by-step explanation:
it states that induced emf of different polarities induces a current whose magnetic field opposes the change in magnetic flux through the coil in order to ensure that original flux is maintained through the coil when current flows in it.
according to Faraday' s law of electromagnetic induction
Where -ve sign due to lenz's law
Emf is the induced voltage also known as electromotive force
N is the number of loops.
dϕ Change in magnetic flux.
dt Change in time.