Question

a charge (Q) is kept just outside the cube at corner . what is the flux through a cube and through a face​

Answer 1

The flux through a cube and through a face​: Q/8ϵ    and Q/24ϵ  

If the charge Q is placed at the corner of the cube , it would be shared between 8 cubes.

Charge for 1 Cube= Q/8

From the perspective of any cube, the charge is touching three of its faces.So area and electric vector would be perpendicular to each other.

So flux through the 3 sides touched by the charge Q will be 0.

The amount of flow of flux from the three sides would be equal.

Flux through 1 face=((Q/8)/(3ϵ)  )

=Q/(24ϵ  )

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