Question

A charge $Q$ is placed at the corner of a cube. The electric flux through all the six faces of the cube is:

• A. $\frac{Q}{3{\epsilon }_0}$
• B. $\frac{Q}{6{\epsilon }_0}$
• C. $\frac{Q}{8{\epsilon }_0}$
• D. $\frac{Q}{{\epsilon }_0}$

Answer 1

Answer: (C)

$\frac{Q}{8{\epsilon }_0}$

The charge is kept at a corner of a cube so it can be visualised as being at the centre of a cube of double its side i.e.,comprising of 8 such cubes kept besides and top of each other.
Thus contribution to each smaller cube will be $\frac{Q}{8{ϵ}_0}$.