# RLC phase angle - Multisim

1. Apr 24, 2015

### dwn

1. The problem statement, all variables and given/known data
This is actually a lab I'm performing on Multisim. I've recreated a circuit that I build in lab class , but I'm not getting the output I need. I am trying to calculate the V and phase angle across each component. I already have the measurements found form the class lab. In addition to the oscilloscope terminal B not working, I'm not sure how to calculate the phase angle across the cap and inductor.

I know that each angle is -90 for cap and +90 for inductor.
2. Relevant equations
See images

3. The attempt at a solution

Measured values, but not sure how to apply to phase angle equation to find capacitor and inductor phase angles.

2. Apr 24, 2015

### dwn

Nevermind the multisim question, I figured out what I was doing wrong. As far as calculating the phase angles: do I measure the distance between the source wave and the component wave (wave/division) then take the tan-1(dV/R)?

3. Apr 24, 2015

### Zondrina

The equation you have been given is for the phase of the entire circuit.

I'm not sure, but you may be looking for a "phase difference". In that case $\phi = \omega \Delta T = 2 \pi f \Delta T$ should be all you need.

4. Apr 24, 2015

### dwn

My second port is no longer flat-lining, and I know I have to move the placement of the resistor in the circuit in order to get a reading of it on the oscilliscope, but the scope doesn't match my Vr measurement from lab, instead its looks closer to what I got for the Vcap measure. Could someone please explain this to me?

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Last edited: Apr 24, 2015
5. Apr 24, 2015

### Staff: Mentor

You have B monitoring the capacitor voltage (between the capacitor and earth), and the display shows this voltage lagging the signal voltage.