Question

1. An electrostatic field line is a continuous curve. That is, a field line cannot have sudden breaks. Why not?
2. Explain why two field lines never cross each other at any point?

Answer 1

(a)

As, `vecF_(OA) = -vecF_(OC) or vecF_(OA) + vecF_(OC) = 0`  ...(i)

Therefore, at zero, the net force on the charge is + 1 µC.

`vecF = vecF_(OA) + vecF_(OC) + vecF_(OB) + vecF_(OD) or vecF = 0`

A field line cannot have abrupt breaks because a test charge in motion moves continuously and does not jump from one position to another.

(b) Two electric field lines can never intersect each other. If they were to cross, there would be two tangents at the point of intersection, indicating two different directions of the electric field at the same point, which is impossible.