Question: What is the energy stored in a capacitor of 5 µF charged to a voltage of 10 V?

Options:

1. 0.25 mJ
2. 0.5 mJ
3. 0.75 mJ
4. 1 mJ

Correct Answer: 0.25 mJ

Solution:

Energy (U) = 0.5 * C * V² = 0.5 * 5 x 10^-6 F * (10 V)² = 0.25 mJ.