Electric Field Lines Direction of E

Description:

The tangent drawn at any point on the curve represents the direction of electric field at that point.

Direction of electric field at any point on the electric field lines can be found by placing a test ‘q’ at that point. The direction in which test charge experiences force gives the direction of electric field at that point. So direction of force experienced by a test charge  and direction of electric field at every point is always same.

The tangent in the figure below shows the direction of force on a test charge and also the direction of electric field.