Solve Circuits Homework: V=IR, 12V & 24V, 2-8 Ohms

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The discussion centers on solving a circuit homework problem using Ohm's Law (V=IR) with given voltage and resistance values for various resistors. The user calculates the current for R1 as 6 A and for R2 as 3 A, confirming that R1 and R2 are in parallel and share the same voltage of 12 V. The total current from the battery is determined to be 9 A by summing the currents through R1 and R2. The user then attempts to find the equivalent resistance of the circuit using the formula for resistors in parallel and series. The conversation emphasizes the importance of understanding voltage drops across parallel resistors and the next steps in solving the circuit.
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Homework Statement



http://img130.imageshack.us/img130/2366/capturewvb.jpg"

Homework Equations



V=IR

The Attempt at a Solution


Given Information
V I R
Battery
R1 12 V 2 ohm
R2 4 ohm
R3 24 V 4 ohm
R4 8 ohm

I can calculate the current of R1
V = IR
I = V/R
I = 12 V/2 = 6 A = I1

pl if I'm correct sense R1 and R2 are in parrallel and right next to the battery they should share the same voltage?

R2 = 12 V
from which I can calculate the current
V = IR
I = V/R = 12 V / 4 ohm = 3 A = I2

now the current for the whole batter should just be I1 + I2? = 6 A + 3 A = 9 A = I battery

I can fidn the R battery by doing

(1/R1 + 1/R2)^-1 + (1/R3 + 1/R4)^-1 = (1/2 + 1/4)^-1 + (1/4 + 1/8)^-1 = 4 ohm = R battery

am i doing this right were do i go from here?
 
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Find the equivalent resistance of both of the two resistors in parallel then you'll have a circuit with two resistors in series and you should be able to find what you need to find.

The voltage drop across resistors in parallel will be equal but the current will not.
 
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