Electric field lines are an imaginary construct used to represent the strength and direction of the electric field at any point in space. They are drawn as lines that emanate from a positive charge and terminate at a negative charge. The density of the lines represents the strength of the electric field, with closer lines indicating a stronger field.


Conductors are materials that allow the flow of electric charge. When a conductor is placed in an electric field, the charges within the conductor redistribute themselves such that the electric field inside the conductor is zero. This means that the electric field lines passing through the conductor must be perpendicular to the surface of the conductor.


The reason for the perpendicularity of electric field lines to the surface of a conductor can be explained in terms of the behavior of charges in a conductor. When an electric field is applied to a conductor, the charges within the conductor experience a force that causes them to move. As the charges move, they create their own electric field that opposes the applied field. This is known as the induced electric field.

The induced electric field within the conductor is strongest at the surface and decreases towards the interior. This means that the charges on the surface of the conductor experience a greater force than those in the interior. As a result, the charges on the surface redistribute themselves such that the induced electric field cancels out the applied field.

Since the electric field inside the conductor is zero, any electric field lines passing through the conductor must be perpendicular to the surface. This ensures that the component of the field parallel to the surface is zero, as any such component would cause charges to move and create an induced field.


In conclusion, the perpendicularity of electric field lines to the surface of a conductor is a result of the behavior of charges in a conductor. As the induced electric field within the conductor cancels out the applied field, any electric field lines passing through the conductor must be perpendicular to the surface.