Question

Which of the following statements is correct?

(a) An electric field is a scalar quantity

(b) Electric field lines are at 45 degrees to the equipotential surfaces

(c) The surface of a charged conductor is equipotential

(d) Field lines due to a point charge are circular

I got this question by my college professor while I was bunking the class.

My doubt is from Equipotential Surfaces topic in chapter Electrostatic Potential and Capacitance of Physics – Class 12

Answer 1

Correct choice is (c) The surface of a charged conductor is equipotential

Easiest explanation: In conductors, charges are equally distributed over the surface of the conductor. Therefore the potential throughout the surface is the same, i.e. equipotential. The electric field is a vector quantity and the field lines cut the equipotential surfaces at 90 degrees. The field lines due to a point charge are radial.