Page 22 - Electrostatics 11
P. 22
Grade 11 © GC Shiba
Let +Q charge enclosed by an arbitrary shape surface is shown in figure.
Total electric flux through this surface is
ℎ
=
∈ 0
∴ =
∈ 0
Proof for spherical surface:
Consider a +Q charge at the center of a sphere of radius r. The electric
intensity at the surface of sphere is
=
4 2
0
1
= Where = 4 = ℎ
2
0
or, E . A =
∈ 0
∴ =
∈ 0
Applications of Gauss Theorem:
In actual practice, we can never have a point charge, rather we do have
charge bodies having different shapes. Coulomb law cannot be applied directly to
calculate the electric field having different shapes of charge bodies. In such
situations, Gauss theorem is applicable.
22 Electrostatics
