Question

total flux passing through the centre of cube

Answer 1

This forms the basis for Gauss' law, which holds that the total electric flux through a surface is proportional to the enclosed charge. ... A charge q is split by one face of a cube. What is thetotal electric flux through the cube? It is not easy to compute the electric fluxdirectly using the definition.

Answer 2

Total flux passing through the centre of cube
$q \div epsilon \: not$