16. Two identical particles, each with charge q, are placed onthe x axis, one at the origin and the
other at x = 5 cm. A third particle, with charge –q, isplaced on the x axis so the potential
energy of the three-particle system is the same as thepotential energy at infinite separation. Its
x coordinate is:
A) 13 cm B) 2.5 cm C) 7.5 cm D) 10 cm E) –5 cm