Is it even possible to work out the value of R??

thepipersson1980 · 2014-08-22 22:51:15

Ok, so I know this more electronic than maths but I'm guessing you guys might have a logical way of thinking about it???

So my tutor has asked me to calculate impedance Z of a series circuit and all the info I had was,

A capacitor with the value of 300 uF
A inductor with a 800 mH

From there I have calculated the resonant frequency which is 10.3Hz AND the capacitive reactance which is 51.50 Ohms

So , what I have now is this;

R = Unknown
L = 800 mH
C = 300 uF
F = 10.3 Hz
Xc = 51.50
Xl = Unknown
W = 2pieF

Is it possible to calculate Impedance Z if I do not know the value of the resistor? and if so how???

Z= sqrt R^2 + (Xl - Xc)^2

I know this wont be everyone's cup of tea but I'm just praying that one of you guys can help??

Many thanks in advance, even if it was just taking the time to look and on another note I apologize for my lack of understanding of maths, this course I have nearly done bar this question, has encouraged me to enroll at collage to brush up.... it has been 20 years though
Tom

Last edited by thepipersson1980 (2014-08-22 22:56:04)

bobbym · 2014-08-22 23:39:06

Hi;

Without knowing Xc and R we can not get a number for Z.

thepipersson1980 · 2014-08-23 00:05:38

Sorry the value of Xc I have put down, I think you mean Xl which is easy to work out as it is just Xl = WL,

I personally don't think this can be done but I think I need to find someone who is as clever as you guys are with maths, but also understands electronics it might be a big ask but is worth an ask

bobbym · 2014-08-23 00:14:32

Yes, I meant Xl. You are saying it is W x L?

thepipersson1980 · 2014-08-23 01:29:41

yes W*L = Xl

bobbym · 2014-08-23 01:37:24

The equation looks like this?

thepipersson1980 · 2014-08-23 05:19:35

Yes that is correct! sorry for the random replies I'm at work at the moment

bobbym · 2014-08-23 12:51:53

Hi;

To get the impedance we still need to know one more thing, what is R?

ShivamS · 2014-08-23 12:58:21

He doesn't know. That's the problem.

bobbym · 2014-08-23 13:06:30

Hi;

So unless he can work out R from what he already knows in post #1 that is as far as we can go.

Is there a formula that links R with any of those known values?

thepipersson1980 · 2014-08-24 02:04:21

Not without a value for R or I think it could be possible if you had a voltage but as I only have a frequency, I don't think it would be possible... That said this is all new to me so it could be, but I doubt it

bobbym · 2014-08-24 04:48:07

Then at least you have an answer. It can not be done.

thepipersson1980 · 2014-08-25 03:18:11

Yes, many thanks for your help/second opinion... much appreciated

bobbym · 2014-08-25 03:19:26

Hi thepipersson1980;

Welcome to the forum.

Math Is Fun Forum

#1 2014-08-22 22:51:15

Is it even possible to work out the value of R??

#2 2014-08-22 23:39:06

Re: Is it even possible to work out the value of R??

#3 2014-08-23 00:05:38

Re: Is it even possible to work out the value of R??

#4 2014-08-23 00:14:32

Re: Is it even possible to work out the value of R??

#5 2014-08-23 01:29:41

Re: Is it even possible to work out the value of R??

#6 2014-08-23 01:37:24

Re: Is it even possible to work out the value of R??

#7 2014-08-23 05:19:35

Re: Is it even possible to work out the value of R??

#8 2014-08-23 12:51:53

Re: Is it even possible to work out the value of R??

#9 2014-08-23 12:58:21

Re: Is it even possible to work out the value of R??

#10 2014-08-23 13:06:30

Re: Is it even possible to work out the value of R??

#11 2014-08-24 02:04:21

Re: Is it even possible to work out the value of R??

#12 2014-08-24 04:48:07

Re: Is it even possible to work out the value of R??

#13 2014-08-25 03:18:11

Re: Is it even possible to work out the value of R??

#14 2014-08-25 03:19:26

Re: Is it even possible to work out the value of R??

Board footer