Question: What is the electric potential energy of a system of two charges, +1 µC and -1 µC, separated by 0.1 m?
Options:
Correct Answer: -0.09 J
Solution:
Potential energy U = k * q1 * q2 / r = (8.99 x 10^9 N m²/C²) * (1 x 10^-6 C) * (-1 x 10^-6 C) / 0.1 m = -0.09 J.