# What is the electric field of an infinite plane?

## What is the electric field of an infinite plane?

Figure 1: A charged infinite plane can be considered to be made up of an infinite number of point charges. The electric field at a point can be found by superposition of the electric fields coming from each of the point charges. Electric fields are linear, which means they obey the principle of superposition.

What is the electric field due to an infinite line of charge?

The electric field of an infinite line charge with a uniform linear charge density can be obtained by a using Gauss’ law. Considering a Gaussian surface in the form of a cylinder at radius r, the electric field has the same magnitude at every point of the cylinder and is directed outward.

What is the field symmetry of a plane sheet of charge?

A cylindrical Gaussian surface with base area A and axis perpendicular to the charged sheet is used to find the field. Planar symmetry means that the charge distribution does not change if we slide it in any direction parallel to the sheet.

### Why the electric field outside an infinite charged sheet is constant?

The enclosed charge is the same regardless of the length of the cylinder, so the flux through the ends must be also. Therefore the electric field is the same at any distance from the sheet.

Does distance matter for electric field?

Amazingly, the field expression contains no distance term, so the field from a plane does not fall off with distance! For this imagined infinite plane of charge, it doesn’t matter if you are one millimeter or one kilometer away from the plane, the electric field is the same.

What is relation between field and distance for an infinite line charge?

-Electric field due to a line charge: E=2kλr where λ is the line charge density of the line charge and r Is the distance of the point from the charge. – Ohm’s law: J=σE where J is the current density and σ is the electrical conductivity and E is the electric field.