Question

Gauss law and it's application

Answer 1

Gauss's Law. The total of the electric flux out of a closed surface is equal to the charge enclosed divided by the permittivity. The electric flux through an area is defined as the electric field multiplied by the area of the surface projected in a plane perpendicular to the field.
Applications of Gauss's Law. Gauss's Law can be used to solve complex electrostatic problems involving unique symmetries like cylindrical, spherical or planar symmetry. .

Electric Field due to Infinite Wire
Electric Field due to Infinite Plate Sheet

Electric Field due thin Spherical Shell

Electric Field Outside the Spherical Shell

Electric Field Inside the Spherical Shell

.. We apply Gauss's Law in following way: Choose a Gaussian surface, such that evaluation of electric field becomes easy.

Gauss’s Law can be used to solve complex electrostatic problems involving unique symmetries like cylindrical, spherical or planar symmetry. Also, there are some cases in which calculation of electric field is quite complex and involves tough integration. Gauss’s Law can be used to simplify evaluation of electric field in a simple way.

We apply Gauss’s Law in following way:

Choose a Gaussian surface, such that evaluation of electric field becomes easy

Make use of symmetry to make problems easier

Remember, it is not necessary that Gaussian surface to coincide with real surface that is, it can be inside or outside the Gaussian surface