# Series connection of capacitors

I have some questions for the series connection of capacitors. It would be great if someone could help me get these.

What will happen for the below cases when you have 2 capacitors in series and 2 supplies connected to the extreme ends-

simulate this circuit – Schematic created using CircuitLab

1. When the supply V1 is a fixed voltage V1 and supply V2 is a fixed voltage V2. What will be the charge and the intermediate node voltage Vb?

2. When the supply V1 is ramping from 0 to a voltage Vs and supply V2 is a fixed voltage Vs. What will be the charge and the intermediate node voltage Vb here?

3. For case 2, When there is some initial charge on any capacitor , say C1 has Q_ini charge, how will the individual charge and intermediate voltage Vb get affected?

• Make your life easier and replace the supplies with a single one supplying the sum of the two (or a difference considering the polarity). The reference can be added/subtracted later if you are really interested in the potential values of Va/b/c w.r.t. to your marked ground. Mar 26, 2019 at 17:14
• Series capacitors calculate like parallel resistances... Mar 26, 2019 at 17:16
• 1) Vb will be undefined, it can be anything initially. Mar 26, 2019 at 18:02
• @EugeneSh. The 2 supplies need to be separate. The case 2 is more of an actual use case.
– ags
Mar 27, 2019 at 3:33
• @Neil_UK Yes can be anything initially. But once i am applying the voltages (say for the ramping case) the charge has to change for the caps right?
– ags
Mar 27, 2019 at 3:35