charges on all the plates will have the same magnitude.
If the top and bottom capacitors have capacitances of C 1 and C 2 , respectively, then
the potential difference across the top capacitor is ∆V 1 = Q/C 1 , and the potential
difference across the bottom capacitor is ∆V 2 = Q/C 2. The total potential difference
across the combination is ∆V 1 + ∆V 2 , which equals ∆V. Therefore, the equivalent
capacitance, CS, must be