Electronics > Beginners

Can superposition principle be applied on capacitor?

(1/3) > >>

sevenofnine33:
I saw someone solve a DC circuit by applying superposition to capacitor and voltage source. The circuit is given in the picture. When shoring voltage source he treated capacitor as a voltage source, and when 12V was input, capacitor was an open circuit. Capacitor has some initial voltage.

My solution was to find current trough the capacitor, meaning that same current flows trough 20Ohm resistor. Then finding voltage for that resistor. Writing KVL to find voltage at middle node, and then dividing that voltage with resistance value to get the current trough 100Ohm resistor.

Which one is correct, since we get different values?

soldar:
I am not sure I understand your question. Witha DC voltage the steady state current through the capacitor is zero. From connection time the capacitor will charge exponentially to 12/5 volts. Is this what you are looking for?

From the perspective of the capacitor that circuit behaves the same as the one I attach.

Benta:
Generally, you can not use superposition when calculating a circuit with capacitors or inductors, you'll need to set up the differential equation. In special cases, superposition might be possible, but you'll need to define the limitations precisely.

sevenofnine33:
This was his solution. I'm wandering if this is correct?

sevenofnine33:
And this is the question:

Navigation

[0] Message Index

[#] Next page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod