JEE Main202313 Apr 2023Morning ShiftPhysicsElectromagnetic WavesActual
Which of the following Maxwell’s equation is valid for time varying conditions but not valid for static conditions:
Options
- A∮ B → · d l → = μ 0 I
- B∮ E → · d l → = 0
- C∮ D → · d A → = Q
- D∮ E → · d l → = - ∂ ϕ B ∂ t
Correct answer
D. ∮ E → · d l → = - ∂ ϕ B ∂ t
Step-by-step solution
Maxwell’s four equations describe the electric and magnetic fields arising from distributions of electric charges and currents, and how those fields change in time. The equations are as follows: ∮ E → · d A → = q ε 0       . . . 1 ∮ B ⇀ · d A ⇀ = 0       . . . 2 ∮ E ⇀ · d l ⇀ = - ∂ ϕ B ∂ t       . . . 3 ∮ B ⇀ · d l ⇀ = μ 0 I       .