Question

A point charge of 2uc is at the centre of cubic gaussian surface 9 cm in edge what is net electric flux through the surface

Answer 1

If you are simply asking about the net electric flux through the surface, then it will simply given by q/ε₀, as what said by the Gauss law.

According to the Gauss law, net electric flux through an closed surface(Gaussian surface) containing an charge inside of it, is 1/ε₀ times the net charge.

Since, the Cube is closed, thus net electric flux inside of it is,

   Φ = q/ε₀

  Φ = 2 × 10⁻⁶/(8.85 × 10⁻¹¹)

 ∴ Φ = 2.25 × 10⁴ Nm².

''This shows that net electric flux does not depends upon the size of the Gaussian surface.''

Answer 2

Explanation:

Net electric flux (ΦNet) through the cubic surface is given by,

Where, ∈0 = Permittivity of free space

= 8.854 × 10^−12 N^−1C2 m^−2

q = Net charge contained inside the cube = 2.0 μC = 2 × 10^−6 C

∴

= 2.26 × 10^5 N m^2 C^−1

The net electric flux through the surface is 2.26 ×10^5 N m^2C^−1.