Question: What is the potential energy of a system of two charges +3μC and -5μC separated by 0.3m?
Options:
Correct Answer: -0.45 J
Solution:
Potential energy U = k * q1 * q2 / r = (9 × 10^9) * (3 × 10^-6) * (-5 × 10^-6) / 0.3 = -0.45 J.