Connecting capacitors in series has the effect of decreasing the total
capacitance (this is the opposite of connecting resistors or inductors
Two capacitors of equal value connected in series essentially doubles
the distance between the conducing plates. However, the plate area
remains the same.
The capacitors in series on the left essentially act like this
capacitor. It has the same plate area as each of the capacitors on the
left but the distance between the plates is twice the distance of each
capacitor on the left.
To calculate the total capacitance of
capacitors connected in series use the same formula that is used for
resistors in parallel. You can use the product-over-sum method or the
reciprocals method, as below.
Capacitors Part 3 - Capacitors in Series and Parallel