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Which of the following Maxwell's equation is valid for time varying conditions but not valid for static conditions:
- ∮ B · dℓ = μ0 I
- ∮ E · dℓ = 0
- ∮ D · dA = Q
- ∮ E · dℓ = - dΦB / dt
Correct answer: ∮ E · dℓ = - dΦB / dt
Solution
This equation represents Faraday's law of electromagnetic induction, which states that a changing magnetic field induces an electric field. It is specifically applicable under time-varying conditions, unlike the other options that hold true for static situations.
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