Give characteristics of electric field lines.

$(i)$ A tangent at any point on electric field line gives direction of electric field at that point.

$(ii)$ Two electric field lines never intersect each other. If they do so, then there will be two tangents at the point of intersection and hence two directions of electric field at the same point, which is not possible. Hence, two field lines can never cross each other.

$(iii)$ The distribution of electric field lines in any region of field gives intensity of field in that region.

$(iv) $Field lines of uniform electric field are equidistant and parallel to each other.

$(v)$ Field lines of stationary electric charge do not form closed loops.

In practice, number of field lines passing through any region of field is controlled such that, number of field lines passing through unit area which is normal to field line at that point is proportional to the intensity of the given field.