Resistors in seris and in parallel

AI Thread Summary
The discussion focuses on calculating voltage, resistance, and current for resistors in series and parallel. Initial calculations for total resistance yielded 77.92 ohms, with a total current of 1.54A. However, there were discrepancies in voltage readings for individual resistors, particularly the 32-ohm resistor, which was noted as incorrect. To accurately find voltage across parallel resistances, the equivalent resistance should be multiplied by the total current. The conversation emphasizes the importance of using Ohm's Law to determine individual currents and voltages correctly.
Moninder
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I have this question
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I need to Find Voltage, Resistance and Current in all resistors and total.
This is what I did so far.
Added 13ohms +15 ohms, then took all 3 of those and made it into one, whihc gave me 7.2258ohms.
Did the same for the 72 and 45 to get 27.7 ohms.
Then found the total resistance as 77.92 ohms. Found I total , current to be 1.54A
And for the 19ohm resistors I got V=29.26V I=1.54A
For 24ohm, V=36.96 I=1.54A
And I think for the 32 ohm V=29.26 I=0.91A
For 72ohm and 45 ohm V=27.7ohm and if that is it, should total current equal 1.54 instead of 0.88A?
 
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I take it we are supposed to psychically devine what voltage is across the string? :smile:
 
phinds said:
I take it we are supposed to psychically devine what voltage is across the string? :smile:

I just did, it's 120 V.

The voltage across the 32V resistance is wrong.
To determine the voltage across parallel resistances, you first use ohms law on the equivalent reistance, so you multiply the equivalent resistance (wich was 7.2258 ohm), with the total current, to get the voltage across all the parallel resistances. Then you find out all the currents through individual resistances by using ohms law on the individual resistances.

This goes for the 72 ohm in parallel with 45 ohm too.
 
So I know that electrons are fundamental, there's no 'material' that makes them up, it's like talking about a colour itself rather than a car or a flower. Now protons and neutrons and quarks and whatever other stuff is there fundamentally, I want someone to kind of teach me these, I have a lot of questions that books might not give the answer in the way I understand. Thanks

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