Capacitors in Series & Parallel
- Recall the formula for the combined capacitance of capacitors in series:
- In parallel:
Ctotal = C1 + C2 + C3 ...
Worked example
Three capacitors with capacitance of 23 μF, 35 μF and 40 μF are connected as shown below
Calculate the total capacitance between points A and B
Step 1: Calculate the combined capacitance of the two capacitors in parallel
Capacitors in parallel: Ctotal = C1 + C2 + C3 …
Cparallel = 23 + 35 = 58 μF
Step 2: Connect this combined capacitance with the final capacitor in series
Step 3: Rearrange for the total capacitance
Exam Tip
Both the combined capacitance equations look similar to the equations for combined resistance in series and parallel circuits. However, take note that they are the opposite way around to each other!
