Case: Read the passage and answer the following questions

Conductors contain mobile charge carriers. In metallic conductors, these charge carriers are electrons. In a metal, the outer (valence) electrons part away from their atoms and are free to move. These electrons are free within the metal but not free to leave the metal. The free electrons form a kind of ‘gas’; they collide with each other and with the ions and move randomly in different directions. In an external electric field, they drift against the direction of the field. The positive ions are made up of the nuclei and the bound electrons remain held in their fixed positions.

What will be the direction of the electrostatic field on the surface of the charged conductor?

Normal to the surface

Electric field is defined to be the gradient of potential and the surface of a conductor has a constant potential. Therefore, there is no field along the surface of the conductor and hence, the electrostatic field at the surface of a charged conductor should be normal to the surface at every point.