Electric Field Lines
Electric field lines are imaginary lines in a region of space or time along which a free positive charge would move if allowed to do so.
Properties of Electric Field Lines
- They originate from positive charges and terminate at negative charges.
- They do not form closed loops.
- They do not terminate in space.
- The number of electric field lines from a charge is directly proportional to the magnitude of charge.
- The field lines are symmetric about the line joining two charges.
- The density of field lines gives the magnitude of the field.
- The field lines are perpendicular to the surface of charge.
- The tangent drawn on a field line gives the direction of the electric field at that point.
- Two electric fields of lines can never intersect each other because if they do so then at the point of intersection there will be two tangents and hence to directions of the electric field will be formed which is not possible.
- The electric field lines are repelled by positive charge and attracted by the negative charge.
- Parallel, straight, equispaced field lines represent a uniform electric field.
- The electrostatic condition electric field inside a conductor is absent.
- electric field lines are always perpendicular to the surface of a conductor.
- Near and far-field lines are formed.
- The electric lines of force do not pass through a conductor this indicates that the electric field inside a conductor is always zero.
- The electric lines of force have a tendency to contract in length like a stretch elastic strength this explains the attraction between the opposite charges.
- The relative closeness of the electric field line of force in different regions of this indicates the relative strength of the electric field in different regions.