Calculating Current in a Mixed Series and Parallel Circuit

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The discussion revolves around calculating current and voltage in circuits that have both series and parallel components. Participants clarify the application of Ohm's Law (V=IR) and the rules for voltage and current in series and parallel configurations. There is confusion about how to effectively use total resistance (Rt) when dealing with mixed circuits, especially in determining current through individual resistors. Suggestions include calculating total current first and then using proportions to find individual currents in parallel branches. The conversation emphasizes the need to understand the distinction between calculating current through and voltage across resistors in such circuits.
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just a quick question about ohms law (v=ir) concerning when there is a parallel and a series in the same circuit. i know the rules like in a parallel, v total is v1+v2... and in a series it is 1/v+1/v2=1/vt. and that's the opposite for Current. but what do i do when there is a series and a parallel in the same question.

heres a basic question i just made. sorry its a bit dirty.

i just changed the question to help understand the concept better

The problem i have is that i can find Rt but i have no idea what to do with it because... there are 2 different things
 

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Looks like homework to me.

Looking at the questions

What do you mean calculate current from R1 etc and voltage from R1 etc?

You calculate current through a resistor and the voltage across a resistor.

If you have to calculate these for each resistor the effective resistance Rt will not help you.
 
Studiot said:
Looks like homework to me.

Looking at the questions

What do you mean calculate current from R1 etc and voltage from R1 etc?

You calculate current through a resistor and the voltage across a resistor.

If you have to calculate these for each resistor the effective resistance Rt will not help you.

so just replace from with through then :D. and how do i find the voltage and current Through these resistors without effective resistance?
 
actually, could i just find the Rt then find the Current in total. and then like separate it using proportions? like say the Rtparallel was 2 and the Rtseries was 2. and Rt in all was 4. Let's say V=8. I am just making this up now, so you don't get confused with the pic on top. so i could do V=IR->8=I*4. Itotal=2. i is the same in a series so each resistor in the series is I=2A and for the Parallel i can do the It=I1+I2... i think i got it.
 
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That's pretty much right. You would still have to figure out what I1 and I2 are.
 
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