Energy stored in a capacitor
How much energy is stored in a 10 μF capacitor charged to 10 V?
Answer B: explanation for every choice
A
This uses ½CV, which is half the charge, not energy.
B
Correct. U = ½CV² = ½(10 × 10⁻⁶)(10²) = 5 × 10⁻⁴ J = 0.5 mJ.
C
This leaves out the ½.
D
This uses 10 mF instead of 10 μF.
TakeawayU = ½CV² = ½QV = Q²/2C.
Equation usedCapacitance and stored energy
Next question →Reviewed 2026-11-05 by a medical student. Spot an error? Report it with question ID cp81.