charge q is placed at vorner of a cube.the electric flux through all faced of cube is?

At the point when a charge q is set at the side of the 3D shape it implies the flux is disseminated among 8 3D squares of same measurement in light of the fact that in one corner there can be 8 cubes.(You need to envision it, Similar to strong state where one corner iota is shared by 7 other cross section. Add up to grid 3D squares =8). 

So the flux connected with one solid shape is (1/8)q/e

The flux leaving the charge will pass just to 3 appearances of the block since alternate countenances are parallel. 

In this way, Flux=1/3 x 1/8 x q/e

=1/24e