When different rated capacitors are connected in parallel, the total capacitance is which of the following?

• A. less than the capacitance of the smallest capacitor.
• B. equal to the capacitance of the largest capacitor.
• C. equal to the sum of all the capacitances.
• D. equal to the average of the capacitances.

Answer: (C)

When capacitors are connected in parallel, they all share the same voltage, and the total storage comes from simply adding up what each one can hold at that voltage. For each capacitor, the charge it stores is Q = C V. With the same V across all capacitors, the total charge is Q_total = (C1 + C2 + ... ) V. Since total capacitance is defined by C_total = Q_total / V, it follows that C_total = C1 + C2 + ... . So the total capacitance is the sum of the individual capacitances. For example, a 4 μF and a 6 μF capacitor in parallel yield 10 μF. The other options would imply reductions or averaging, which don’t happen in parallel connections.