# Phase difference between Source and Capacitor Voltage

#### SalmanKn

Joined Mar 15, 2023
4
Hello people, I'm the dumbest guy on planet earth and the point i am trying to understand is why the source voltage and capacitor voltage are 180 degree out of phase? Or am i making some kind of mistake in measurement.

#### ericgibbs

Joined Jan 29, 2010
18,032
Hi S,
Welcome to AAC.
There is a phase difference between the voltage and the current for a Resistor Capacitor circuit, not 180 degrees.

To remember V/I phase difference for Capacitors and Inductors, use the word CIVIL.

C
urrent before Voltage for a Capacitor, and Voltage before Current for an Inductor.

E

#### MrChips

Joined Oct 2, 2009
29,236
Your simulation is measuring opposite legs of the AC source.
The capacitor has nothing to do with your observations. Remove the capacitor and the results remain the same.

#### crutschow

Joined Mar 14, 2008
32,915
Obviously with the capacitor connected directly to the source, the two voltages must be the same.
The capacitor current, however, is 180° out-of-phase with the applied voltage.

#### SalmanKn

Joined Mar 15, 2023
4
Your simulation is measuring opposite legs of the AC source.
The capacitor has nothing to do with your observations. Remove the capacitor and the results remain the same.
Thanks, I figured that out shortly after posting

#### SalmanKn

Joined Mar 15, 2023
4
Hello people, I'm the dumbest guy on planet earth and the point i am trying to understand is why the source voltage and capacitor voltage are 180 degree out of phase? Or am i making some kind of mistake in measurement. View attachment 293645
Thanks everyone for taking the time to reply, I now know what the problem was

#### MrChips

Joined Oct 2, 2009
29,236
Thanks everyone for taking the time to reply, I now know what the problem was
Note that when a member finds the solution to a problem, they could very well be helping others with the same or similar problem.
That is what AAC is all about. We each take something and we give back something in return.

Please post what you have discovered and what was the solution to the problem.

#### SalmanKn

Joined Mar 15, 2023
4
Note that when a member finds the solution to a problem, they could very well be helping others with the same or similar problem.
That is what AAC is all about. We each take something and we give back something in return.

Please post what you have discovered and what was the solution to the problem.
Sure,
I was looking at two waveforms, one was the coming from positive leg of AC source while the second was coming from the negative leg of AC source, The second (blue) signal was not actually the voltage across capacitor.

#### MrChips

Joined Oct 2, 2009
29,236
Sure,
I was looking at two waveforms, one was the coming from positive leg of AC source while the second was coming from the negative leg of AC source, The second (blue) signal was not actually the voltage across capacitor.
Thanks for posting an update.