Circuits with parallel resistors

AI Thread Summary
In a circuit with a 10V battery and three parallel resistors (R1=10ohm, R2=40ohm, R3=50ohm), the voltage across each resistor is 10V, as the voltage remains constant in parallel configurations. For a second scenario with resistors R1=10ohm, R2=20ohm, and R3=500ohm, where R2 carries a current of 100mA, the voltage across R2 is calculated to be 2.0V. Since the resistors are in parallel, R1 also experiences this voltage of 2.0V. The current through R1 is then calculated using Ohm's law, resulting in 200mA. The calculations and reasoning presented in the discussion are confirmed to be correct.
chiurox
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Homework Statement


1) A circuit contains a 10V battery and three resistors in parallel. The resistors have values R1=10ohm, R2=40ohm, R3=50ohm. What is the voltage across each resistor?

2)This time, the 3 resistors in parallel have values R1=10ohm, R2=20ohm, R3=500ohm. The current flowing through R2=100mA. What is the current flowing through R1?


Homework Equations





The Attempt at a Solution


1) 10 V across each, because the voltage is the same across parallel resistors right?

2) I made a V-I-R chart. Since R2 has a current of 100mA and its resistance is 20ohm, then the voltage is 2.0V. Since the resistors are in parallel, the voltage is the same for R1.
So 2volts=I(10ohm)
I=200 mA is this correct?
 
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Hi chiurox,

That looks correct to me.
 
yeah that's absolutely right
 
Oh... ok, I was a bit insecure. thanks
 

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