Gauss’s Law

A charge Q is placed at the centre of a cube. Find the flux of the electric field through the six surfaces of the cube.

State and explain Gauss’s law.

The Gaussian surface ______.

In finding the electric field using Gauss law the formula `|vec"E"| = "q"_"enc"/(epsilon_0|"A"|)` is applicable. In the formula ε₀ is permittivity of free space, A is the area of Gaussian surface and q_enc is charge enclosed by the Gaussian surface. This equation can be used in which of the following situation?

Refer to the arrangement of charges in figure and a Gaussian surface of radius R with Q at the centre. Then

1. total flux through the surface of the sphere is `(-Q)/ε_0`.
2. field on the surface of the sphere is `(-Q)/(4 piε_0 R^2)`.
3. flux through the surface of sphere due to 5Q is zero.
4. field on the surface of sphere due to –2Q is same everywhere.

If the total charge enclosed by a surface is zero, does it imply that the elecric field everywhere on the surface is zero? Conversely, if the electric field everywhere on a surface is zero, does it imply that net charge inside is zero.

Five charges q₁, q₂, q₃, q₄, and q₅ are fixed at their positions as shown in figure. S is a Gaussian surface. The Gauss’s law is given by `oint_s E.ds = q/ε_0`

Which of the following statements is correct?

A charge ‘q’ is placed at the centre of a cube of side l. What is the electric flux passing through each face of the cube?