Question

If three equal charges are placed at the corners of an equilateral triangle, the potential at the center of the triangle will be zero.

(a) True

(b) False

I got this question in an interview for job.

My question is taken from Potential Energy of a System of Charges in division Electrostatic Potential and Capacitance of Physics – Class 12

Answer 1

Right choice is (b) False

Easiest explanation: Electrostatic potential at a distance r from a point charge q is \(\frac {1}{4 \pi \epsilon} * \frac {q}{r}\). Therefore, adding this term three times, we get some positive value, not zero. Therefore, the potential energy at the center of the triangle is positive, not zero.