What is the current relationship between resistors in parallel?

AI Thread Summary
The discussion revolves around a circuit with two 5Ω resistors in series, which are in parallel with another 5Ω resistor, with a total current of 4 amps running through the series. Participants clarify the relationship between the resistors, emphasizing that the voltage drop across the series resistors is the same as that across the parallel resistor. The total current in the circuit is confirmed to be 4 amps, leading to the application of Ohm's law to find the voltage and current through each branch. The importance of understanding the voltage across parallel components is highlighted for solving the problem. The conversation concludes with the acknowledgment of the provided voltage of 20V, simplifying the calculations.
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Homework Statement



I have a circuit with two resistors in series that are in parallel to another resistor. Each resistor is 5Ω. The total current running through the series is 4amps. I need to find the current in the single resistor that is in parallel. What is the relationship among these three resistors in regard to current??

Homework Equations



for series Itotal=I1=I2=I3

The Attempt at a Solution



for parallel Itotal=I1+I2+I3
 
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What is the voltage drop through each branch of resistors in parallel?
 
I believe that something that could be useful here is the fact that voltage is the same across all elements that are parallel to one another in a circuit. I'm just not sure what you mean by the total current running through the series is 4 amps. Do you mean that the total current running through the resistor that is in series with the two resistors in parallel is 4 amps? It would be helpful to see a circuit diagram to answer this question.
 
3inst3in said:

Homework Statement



I have a circuit with two resistors in series that are in parallel to another resistor. Each resistor is 5Ω. The total current running through the series is 4amps. I need to find the current in the single resistor that is in parallel. What is the relationship among these three resistors in regard to current??

Homework Equations



for series Itotal=I1=I2=I3

The Attempt at a Solution



for parallel Itotal=I1+I2+I3
Apply Ohm's law to determine the voltage across the two series resistors.

How is that voltage related to the voltage across the other branch with the single resistor? Apply Ohm's law to determine the current through that branch.

AM
 
The total current running through the series is 4amps.

Thats ambiguous...

1) If you mean the current through the two resistors in series is 4 amps then... Work out the voltage drop across the two in series. The same voltage drop is across the one in parallel.

2) If you mean the total of the current in the whole circuit is 4 amps then.. Work out the equivalent resistance of (5+5)//5 and then use Ohms law to calculate the voltage drop.
 
CWatters said:
Thats ambiguous...

1) If you mean the current through the two resistors in series is 4 amps then... Work out the voltage drop across the two in series. The same voltage drop is across the one in parallel.

2) If you mean the total of the current in the whole circuit is 4 amps then.. Work out the equivalent resistance of (5+5)//5 and then use Ohms law to calculate the voltage drop.


oops, yes, I meant that the current in the whole circuit is 4amps.
ahh... and I completely forgot about voltage...
I am given that ε=20V which makes the question a lot simpler now
& thanks everyone for responding!
 
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