An electric field is a force field that surrounds an electric charge and exerts a force on other charges in its vicinity. The strength and direction of the electric field at a given point can be determined by the magnitude and sign of the nearby charges. The electric field is represented by electric field lines, which depict the direction of the force that a positive test charge would experience at each point.

For example, consider a positive point charge. The electric field lines emanate radially from the charge, indicating that a positive test charge placed at any point around the charge would experience a repulsive force away from it.

Gauss's law is a powerful tool that allows us to calculate the electric field in situations with high symmetry. It states that the electric flux through any closed surface is directly proportional to the enclosed charge. In simpler terms, the net number of electric field lines passing through a closed surface is equal to the net charge enclosed by that surface divided by a constant.

To illustrate this, let's take the example of a uniformly charged sphere. The electric field inside and outside the sphere can be determined using Gauss's law and the symmetry of the system.

Tags: electromagnetism, electric fields, Gauss's law