Physics - Electrostatics Question with Solution | TestHub

Enclosed charge = sigma x disk area cut by the xy-plane: $\varphi =\frac{\sigma \pi (25-c^2)}{{\epsilon }_0}=2\pi (25-c^2)$ for |c|<5, else 0.

(2,0,0) and (4,3,0): $\varphi =50\pi$ (A, D correct). (0,4,0): also $50\pi \ne 30\pi$ (B wrong). (0,2,6): plane misses the sphere, $\varphi =0$ (C correct).