Compound Circuits and resistance in a parallel circuit

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The discussion focuses on calculating the current through resistors R2 and R3 in a parallel circuit with a total resistance of 9.00 Ω and a voltage of 80.0 V. The initial calculation for total current yields 8.89 A. The voltage across R2 and R3 is confirmed to be 26.67 V, which is used to determine the individual currents through each resistor. The final results show that R3 carries 2.22 A and R2 carries 6.67 A. The conversation highlights the importance of understanding compound circuits and applying Ohm's law effectively.
bnosam
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Homework Statement


http://imageshack.us/a/img829/1351/circuite.png
Find the current through R3 and R2.

The resistance of R2 and R3 are 3.00 Ω, so the total resistance should be 9.00 Ω.

I = 80.0 V / 9.00 Ω = 8.89 A

Homework Equations



I = E/R (I think?)

The Attempt at a Solution



Not really sure where to go from here, since this was the first question of this unit and it's a correspondence course and the book doesn't explain compound circuits past a single paragraph.

Any supplemental information or hints you can provide?

Thanks
 
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So far, so good. What's the voltage across R2 and R3?
 
V = I*R

V = (8.89 A) (3.00 Ω) = 26.67 V, right?
 
bnosam said:
V = I*R

V = (8.89 A) (3.00 Ω) = 26.67 V, right?
Good! Now use that to find the current through each resistor.
 
Doc Al said:
Good! Now use that to find the current through each resistor.

Awesome man, thanks a lot.

R3 = 26.67 V / 12.00 Ω = 2.22 A

R2 = 26.67 V / 4.00 Ω = 6.67 A
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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