An electric field is a physical quantity that describes the strength and direction of the force exerted on a charged particle by other charges. It is created by electric charges and can be thought of as the influence of these charges on the space around them.
The electric field value at a distance from a charge can be calculated using the formula E = kQ/r^2, where E is the electric field strength, k is the Coulomb's constant, Q is the charge, and r is the distance from the charge.
The electric field value decreases as the distance from a charge increases. This is because the electric field spreads out in all directions, resulting in a larger area over which the force is applied, thus decreasing its strength.
The electric field value can be affected by the presence of other charges or plates. When multiple charges or plates are present, the electric field values can either add together or cancel each other out, depending on their direction and magnitude.
The electric field value at different distances from a charge depends on the distance and the charge's magnitude. On the other hand, the electric field value at a distance from a plate depends on the charge density of the plate and the distance from the plate. Additionally, the electric field from a charge is radial, while the electric field from a plate is uniform in one direction.