Question: What is the energy stored in a capacitor of 5 µF charged to a voltage of 12 V?

Options:

1. 0.36 mJ
2. 0.60 mJ
3. 0.72 mJ
4. 0.84 mJ

Correct Answer: 0.72 mJ

Solution:

Energy stored U = 0.5 * C * V² = 0.5 * 5 x 10^-6 F * (12 V)² = 0.36 mJ.