Question

An electric charge $q$is placed at the centre of a cube of side $a$ The electric flux through one of its faces is

• A. $\frac{q}{6{ϵ}_0}$
• B. $\frac{q}{6{ϵ}_0{a}^2}$
• C. $\frac{q}{6\pi {ϵ}_0{a}^2}$
• D. $\frac{q}{{ϵ}_0}$

Answer 1

The correct option is A $\frac{q}{6{ϵ}_0}$

Flux through the cube $=\varphi =\frac{q}{{ϵ}_o}$

Since, charge is placed symmetrically and is equivalent to all 6 faces , hence flux through all 6 faces will be equal and the sum of flux through all six face equals the total flux.

Hence, flux through each face $=\frac{q}{6{ϵ}_o}$

Answer-(A)