Question

Write the properties of electric lines of force.

Answer 1

The properties of electric lines of force are:

i) Lines of force start from positive charge and terminate at negative charge.

ii) Lines of force never intersect.

iii) The tangent to a line of force at any point gives the direction of the electric field at that point.

iv) The number of lines per unit area, through a plane at right angles to the lines is proportional to the magnitude of $E$. That is, when the lines of force are close together, $E$ is large and where they are far apart, $E$ is small.

v) Each unit positive charge gives rise to $\frac{1}{{\epsilon }_0}$ lines of force in free space. Hence, number of lines of force originating from a point charge $q$ is $N=\frac{q}{{\epsilon }_0}$ in free space.