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  1. T

    Capacitance of capacitors

    Show us your problem.
  2. T

    Bridge circuit impedance

    Now that I look again at the final result in the image attached to post #1, I see immediately that it's incorrect. If the resistance "b" is not there its value becomes infinite. The final expression given says that if "b" is missing (becomes infinite), the bridge resistance becomes infinite...
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    Bridge circuit impedance

    I know you have Mathematica, so I figured you would have checked the post #1 result. :) I solved it with Mathematica, and the post #1 result appears incorrect.
  4. T

    Bridge circuit impedance

    There is an image attached to post #1 with the problem worked out. You, like me, tend to check results, Have you worked out the solution to the impedance seen at terminals 1 and 3, and compared to the result in the image attached to post #1?
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    Bridge circuit impedance

    Ratch, I think the final result in the image attached to post #1 is incorrect. Have you worked out the impedance seen at terminals 1 and 3, and compared your result with the result in the image?
  6. T

    Finding internal resistance of a cell/battery

    It's fairly well explained on page 23 of the Teacher's guide.
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    Maximum Voltage in passive capacitive circuit

    Here's the oldest description of an RC network with gain I know of; page 40 of this old magazine: https://www.americanradiohistory.com/Archive-Tele-Tech/40s/Tele-Tech-1947-04.pdf
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    Maximum Voltage in passive capacitive circuit

    Discussion about this topic: Fialkow, A.D. & Gerst, Irving. (1953). The Maximum Gain of an RC Network. Proceedings of the IRE. 41. 392 - 395. 10.1109/JRPROC.1953.274389. Also: https://ieeexplore.ieee.org/document/4050644 Also...
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    Not understandable ESR value of the capacitor.

    The 0.1 uF capacitor I have in my assortment is marked with the manufacturer--it's Jwco.I found the manufacturer's list of capacitor models here: http://www.jiaweicheng.com/en/productlist/products.html They show several models whose capacitance range goes down to 0.1 uF. My capacitor doesn't...
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    Not understandable ESR value of the capacitor.

    What is the model of ESR meter you're using?
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    Not understandable ESR value of the capacitor.

    If the measurement you got for your 0.1 uF was around 10 ohms then it must be ok, since extrapolating from the data you found of a 0.47 uF max impedance at 23 ohms, 0.1 uF max allowable would be much more than that.
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    Not understandable ESR value of the capacitor.

    Probably the reason you didn't find that value in tables is that 0.1 uF is an uncommonly small value for an electrolytic capacitor. Are you sure it's an electrolytic? You could just replace it with a 0.1 uF film capacitor. I have some 0.1 uF electrolytics only because they were part of a full...
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    Electrotechnic exercise (help)

    You used 3 equations (i1 and i2 are not asked for) and involved the current source. For short and succinct, apply the voltage divider formula twice, obtaining expressions for the voltage across C3 and across Z, equate them and solve one equation. The current source needn't be involved...
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    Electrotechnic exercise (help)

    You didn't read all the other responses to post #1, did you? I made my careless mistake, and you failed to notice that the capacitors and inductor are not microfarads and microhenries, but rather millifarads and millihenries.
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    Electrotechnic exercise (help)

    There's my mistake. In the table of component values, where it says w = 50 rad/s, I just mentally changed that to 50 Hz, not 50 rad/second. :( This is in Europe right, where the power is 50 Hz? With that change both my solutions will get Z = 2. I also did a mesh solution which also gets Z=2.
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    Electrotechnic exercise (help)

    Looking back at the last thing he said in post #1, "Please help me i'm litterally desperate", that should have been a clue to me that this was a take-home exam. :(
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    Electrotechnic exercise (help)

    Do you see what you did wrong where you show an expression for Iz?
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    Electrotechnic exercise (help)

    First thing he said in the first post was "I took an exam last week.", but English is not his native tongue. Maybe he meant to say "I took home an exam last week." :( I had the impression that the exam was over, he hadn't done well on this problem, and was looking for some followup to improve...
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    Electrotechnic exercise (help)

    I've had a look at your work. It's difficult to follow because some of the subscripts are blurry, but the main problem I see is your calculation of Iz. You got a numerical value, but how can that be when you don't know the value of Z yet? Also, it looks like you're using the current divider...
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    Electrotechnic exercise (help)

    I didn't realize that this was a take-home exam. I thought you had already taken it as an exam in class, so I shouldn't have given you a complete solution right away. Sorry. However, you have shown some work so I don't feel too bad! :) You have made a mistake somewhere in your work. Here's...
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