Induced EMF in Time Varying Magnetic Field – Rankers Physics

Lenz Law: Practice Problem & Solution

Assertion (A): If a closed loop is kept in a space having time varying magnetic field, emf is always induced in the loop. Reason (R): Induced emf in the loop is conservative in nature.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Lenz Law. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion (A) is true: By Faraday's Law of electromagnetic induction, a time-varying magnetic flux (\(\Phi\)) through a closed loop will induce an electromotive force (\(epsilon = -\frac{d\Phi}{dt}\)). Reason (R) is false: The induced electric field and thus the induced emf, arising from a changing magnetic flux, are non-conservative in nature. If they were conservative, the line integral (emf) would be zero.

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