Calculating inductance of an LR and RLC Circuit?

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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, although the method used was questioned due to missing information about the signal at "Ch. 1." Participants emphasized the need for details like the oscilloscope readout and the amplitude settings of the function generator to accurately determine inductance. The conversation highlights the importance of providing complete data for circuit analysis. Accurate calculations depend on understanding both the circuit parameters and the waveform characteristics.
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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