If the electric flux entering and leaving an enclosed surface respectively are ϕ1 and ϕ2 then what is the electric charge inside the surface ?
Answer & explanation
Correct answer: option 4
Flux entering is due to negative charge and flux leaving is due to negative charge.
Net electric flux is (ϕ2−ϕ1).
Charge enclosed is q = (ϕ2−ϕ1)ϵ0