Search this website:

This web page location:

home page  >   Electricity  >   Electric Fields


Electric Fields

point charge, coulombs, electric fields, newtons, electric field

A single electric charge can attract or repel, and it will demonstrate this ability as soon as another charge is brought near it. The ability to attract or repel can be thought of as being stored in the region around the charge. This region is called the electric field of force of the charge. All charged objects have electric fields around them.

Lines of Force

An electric field can be visualized as consisting of imaginary lines called lines of force. Each line corresponds to the path that a positive charge would take if placed in the field on that line. The lines in the field around a positively charged object radiate in all directions away from the object, since the object repels positive charges. Conversely, the lines in the field around a negatively charged object are directed toward the object. If a positive and a negative object are placed near each other, their lines of force connect. If two objects with similar charges are placed near each other, the lines do not connect. Lines of force never cross each other.

Lines of force are only imaginary. Nevertheless, the idea of lines of force helps in visualizing an electric field.

Field Direction

When a charge is placed at any given point in an electric field, it is acted on by a force that tends to push it in a certain direction. This direction is called the direction of the field at that point. The field direction can be represented graphically by the lines of force near an electric charge.

Field Strength

The strength, or intensity, of a field at any point is defined as the force exerted on a charge of 1 coulomb placed at that point. For example, if a point charge of 1 coulomb is subjected to a force of 10 newtons, the electric field is 10 newtons per coulomb at that point. An object with a charge of 5 coulombs would be subjected to a force of 50 newtons at the same point.

Field strength is represented graphically by the closeness (density) of the lines of force. Where the lines are close together, the field is strong. Where they are far apart, the field is weak. Near a charge, the field is strong and the lines are close together. At greater distances from the charge, the field weakens and the lines are not as close together. The field strength values that the lines represent are relative, since a field can be drawn with as many lines as desired.

Article key phrases:

point charge, coulombs, electric fields, newtons, electric field, electric charge, Field Strength, lines of force, closeness, intensity, density, path, strength, object, force, directions, ability, objects, charge, example, region

Search this website: