Understanding Phase Shift in RC Circuits

In summary, the conversation discusses finding the phase angle for a series RC circuit using the equation cosφ = R/sqrt(R^2 + XC^2) and tan(phi) = (XL-Xc)/R. The individual asking for help is unsure of how to use these equations and asks for clarification. Eventually, they are able to find the correct answer with the help of the equation XC = 1/ωC.
  • #1
pat666
709
0

Homework Statement


Pls see the attachment.


Homework Equations





The Attempt at a Solution


Obviously I have B and C correct but for a the only thing I can find is tan(phi)=XL-Xc/R
This seems to be for a series RLC circuit though and I only have RC.
also I know that the current lags the p.d by 900 in an RC circuit but I can't see how I can use this?
any help appreciated.
 

Attachments

  • PF.jpg
    PF.jpg
    25.5 KB · Views: 708
Physics news on Phys.org
  • #2
Phase angle can found by using

cosφ = R/sqrt(R^2 + XC^2)
 
Last edited:
  • #3
I don't know capacitive inductance though?
 
  • #4
pat666 said:
I don't know capacitive inductance though?

Sorry. It should be XC. = 1/ωC
 
  • #5
Thanks that worked, although the answer was negative 89 degrees?
 
  • #6
You can use the equation tan(phi)=(XL-Xc)/R for a series RCL circuit, even for XL=0 as it is the case now.

ehild
 

1. What is a phase angle RC circuit?

A phase angle RC circuit is a type of electrical circuit that contains a resistor (R) and capacitor (C) in series. It is used to analyze the phase relationship between the voltage and current in an AC circuit.

2. How does a phase angle RC circuit work?

In a phase angle RC circuit, the capacitor charges and discharges according to the frequency of the AC input voltage. The resistor limits the current flow, creating a phase shift between the voltage and current. This phase shift is measured in degrees and is used to analyze the circuit's behavior.

3. What are the applications of a phase angle RC circuit?

Phase angle RC circuits are commonly used in electronic devices such as radios, televisions, and computers. They are also used in electrical power systems to control and adjust the power factor, which is important for efficient energy usage.

4. How is the phase angle calculated in an RC circuit?

The phase angle in an RC circuit is calculated using the equation arctan(1/ωRC), where ω is the angular frequency of the AC input voltage, R is the resistance, and C is the capacitance. This equation gives the phase shift in radians, which can be converted to degrees by multiplying by 180/π.

5. How can the phase angle of an RC circuit be adjusted?

The phase angle of an RC circuit can be adjusted by changing the values of the resistor and capacitor. A larger resistor value will result in a larger phase shift, while a larger capacitor value will result in a smaller phase shift. The frequency of the AC input voltage can also affect the phase angle.

Similar threads

  • Introductory Physics Homework Help
Replies
5
Views
5K
  • Electrical Engineering
Replies
27
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
9
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
4K
  • Electrical Engineering
2
Replies
41
Views
3K
  • Introductory Physics Homework Help
Replies
14
Views
4K
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Classical Physics
Replies
7
Views
1K
Back
Top