Calculating inductance of an LR and RLC Circuit?

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SUMMARY

The discussion focuses on calculating the inductance of LR and RLC circuits using a function generator producing a 1000 Hz square wave. For the LR circuit with a resistance of 100 Ohms, the inductance was calculated to be 0.114 mH. The participants also discussed the impact of increasing resistance to 200 Ohms and the necessary equations for the RLC circuit, where capacitance is set to 0.001 microfarads. Key equations referenced include F_0 = 1/(2*pi*sqrt(LC)) and ω^2 = (1/LC)(1 - (C*R^2)/(4L)).

PREREQUISITES
  • Understanding of LR and RLC circuit configurations
  • Familiarity with the function generator and its settings
  • Knowledge of basic circuit equations, specifically those involving inductance and capacitance
  • Ability to interpret oscilloscope readouts
NEXT STEPS
  • Study the effects of varying resistance on inductance in LR circuits
  • Learn how to use the equation F_0 = 1/(2*pi*sqrt(LC)) for RLC circuits
  • Explore the relationship between frequency and inductance in RLC circuits
  • Investigate the impact of waveform amplitude on circuit behavior
USEFUL FOR

Electrical engineering students, circuit designers, and anyone involved in analyzing or designing LR and RLC circuits will benefit from this discussion.

WK95
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Homework Statement


For both the LR and RLC circuit, a function generator is used to create a 1000 Hz square wwave of maximum amplitude.
1) For the following LR circuit, the resistance is set to a 100 Ohms. Determine the inductance, L. How does the inductance vary if the resistance were increased to 200 Ohms[/B]
5WUQFAq.png

2) For the following RLC circuit, the capacitance is set to a 0.001 micro F. Determine the inductance, L.
SBr0Irn.png

Homework Equations


2) F_0 = 1/ (2*pi* sqrt(LC))
ω^2 = (1/LC)(1 - (C*R^2)/(4L))
ω=2*pi*f


3. The Attempt at a Solution

1) I can't find any formulas for this one.
2) For question 2, I don't know which equation should be used. Also, I assume that f=1000Hz. For the second equation, R is the total circuit resistance, C is the capacitance, and L is the inductance.
 
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I've found an equation for question 1.

V=V_0(e^(-Rt/L))
 
For question 1, I got the inductance to be 0.114 mH.
 
bump
 
WK95 said:
For question 1, I got the inductance to be 0.114 mH.
You did? Without knowing anything about the signal at "Ch. 1"? Wow! Show us how!
 
WK95 said:

Homework Statement


For both the LR and RLC circuit, a function generator is used to create a 1000 Hz square wwave of maximum amplitude.
1) For the following LR circuit, the resistance is set to a 100 Ohms. Determine the inductance, L. How does the inductance vary if the resistance were increased to 200 Ohms[/B]
5WUQFAq.png

2) For the following RLC circuit, the capacitance is set to a 0.001 micro F. Determine the inductance, L.
SBr0Irn.png

Homework Equations


2) F_0 = 1/ (2*pi* sqrt(LC))
ω^2 = (1/LC)(1 - (C*R^2)/(4L))
ω=2*pi*f


3. The Attempt at a Solution

1) I can't find any formulas for this one.
2) For question 2, I don't know which equation should be used. Also, I assume that f=1000Hz. For the second equation, R is the total circuit resistance, C is the capacitance, and L is the inductance.
Please give the problem statement as it was given to you. It clear that some critical information is missing.

What does it mean for the function generator to produce a wave of maximum amplitude?

Is it perhaps the wave at Ch. 1 which has to have maximum amplitude?
 
SammyS said:
Please give the problem statement as it was given to you. It clear that some critical information is missing.

What does it mean for the function generator to produce a wave of maximum amplitude?

Is it perhaps the wave at Ch. 1 which has to have maximum amplitude?
Yes, my apologies. I've neglected to include the relevant oscilloscope readout.
zYefk3g.jpg

Vertical Scale: 100mV/DIV
Horizontal Scale: 50 microsecond/DIV

gfg8210-600.jpg

Here is a the function generator used. Notice the AMPL knob to the right. Maximum amplitude means turning it all the way counterclockwise.
 
rude man said:
You did? Without knowing anything about the signal at "Ch. 1"? Wow! Show us how!
Simple. Since I didn't know anything about what was in Ch. 1, I simply had to find it out. You can as well if you were to make the circuit as shown in the initial post.
 
WK95 said:
Simple. Since I didn't know anything about what was in Ch. 1, I simply had to find it out. You can as well if you were to make the circuit as shown in the initial post.
Yeh, but you didn't know L either. You were supposed to find L given Ch. 1.
I see you did post the Ch 1 waveform later. Much better.
It would further be helpful if you provided us with the amplitude of the square-wave generator, although one can estimate L based on the decay profile in Ch. 1.
 

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