Question

Two point charges 10C and -10C are placed at a certain distance. What is the electric potential of their midpoint?

(a) Some positive value

(b) Some negative value

(c) Zero

(d) Depends on medium

I have been asked this question in an online interview.

This interesting question is from Electrostatic Potential due to a Point Charge in chapter Electrostatic Potential and Capacitance of Physics – Class 12

Answer 1

The correct answer is (c) Zero

For explanation I would say: Electric potential is a scalar quantity and its value is solely dependent on the charge near it and the distance from that charge. In this case, the point is equidistant from the two point charges and the point charges have the same value but opposite nature. Therefore equal but opposite potentials are generated due to the charges and hence the net potential at midpoint becomes zero.