Write properities of elecric lines of …

1. The electric lines of force are imaginary lines.
2. A unit positive charge placed in the electric field tends to follow a path along the field line if it is free to do  so.
3. The electric lines of force emanate from a positive charge and terminate on a negative charge.
4. The tangent to an electric field line at any point gives the direction of the electric field at that point.
5. Two electric lines of force can never cross each other. If they do, then at the point of intersection, there will be two tangents. It means there are two values of the electric field at that point, which is not possible. Further, electric field being a vector quantity, there can be only one resultant field at the given point,  represented by one tangent at the given point for the given line of force.
6. Electric lines of force are closer (crowded) where the electric field is stronger and the lines spread out where the electric field is weaker.
7. Electric lines of force are perpendicular to the surface of a positively or negatively charged body.
8. Electric lines of force contract lengthwise to represent attraction between two unlike charges.
9. Electric lines of force exert lateral (sideways) pressure to represent repulsion between two like charges.