# Write some important characteristics of electric field lines

Important characteristics of electric field lines:
(i) A tangent to a field line gives the direction of $overrightarrow{E}$at that point. In fig $overrightarrow{E_1}$ is electric field at P1 and $overrightarrow{E_2}$is a P2.
(ii) The direction in which a free unit positive charge moves is the positive direction of the electric field line.
(iii) The number of field lines linked with a unit area of cross-section is proportional to E.