Question

Why is it necessary that the field lines from a point charge placed in the vicinity of a conductor?

Answer 1

Why is it necessary that the field lines from a point charge placed in the vicinity of a conductor must be normal to the conductor at every point. would have a tangential component which will make electrons move along the surface creating surface currents and the conductor will not be in equilibrium.

Answer 2

As suggested by Marie Ampere, a current carrying conductor exerts a force when a magnet is placed in its vicinity. Similarly, a magnet also exerts equal and opposite force on the current carrying conductor. The direction of force over the conductor gets reversed with the change in direction of flow of electric current