The electric flux through the surface
- in figure (c) is the largest
- in figure (b) is same as figure (c) but is smaller than figure (d)
- is the same for all the figures
- in figure (d) is the least
Solution
Comparing electric flux through surfaces enclosing charge +q: Gauss's Law states that the electric flux $\Phi_E$ through any closed surface depends only on the enclosed charge: $\Phi_E = Q_{\text{enclosed}} / \epsilon_0$.
Since all four surfaces enclose the same charge $+q$, the flux is identical for each: $\Phi_a = \Phi_b = \Phi_c = \Phi_d = q / \epsilon_0$.
The flux is independent of the surface shape or size, rendering options A, B, and D incorrect. The correct choice is C, affirming flux equality across all figures.
Asked in: MHT CET 2025 (05 May Shift 2)