Find the Current passing through the Resistor.

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The discussion focuses on calculating the current through resistors R1 and R5 in a circuit. The original poster shares their equations and notes a typo regarding which resistors they intended to analyze. A key point raised is the need to account for the opposite polarities of the batteries in the circuit when applying Kirchhoff's loop rule. This leads to a clarification that the second voltage (V2) should indeed be subtracted in the equation for the right loop. The conversation emphasizes the importance of correctly interpreting voltage rises and drops in circuit analysis.
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Hi, forum. This is my first time posting and I was curious if someone would mind looking over my work for a problem? I need to find the current passing through R1 and R5, the picture below shows the problem and my attempt at a solution.

In the picture there are three main equations I used, left means the left loop of the circuit, middle means the middle loop, and big right means the loop excluding the left loop. Also at the very bottom the follows sentence gets cut off on the scan, it should say: "I5=3.46A so current passing through R5=3.46"

Thanks in advance for any help and corrections!
EDIT: I had originally put "find the resistance through R1 and R2" This was a typo, I meant find the Resistance through R1 and R5.

http://img707.imageshack.us/img707/8044/scan0003tu.jpg

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In your third loop, comprising V1, V2, R5, and R3, note that the two batteries have opposite polarities; as you traverse the loop, you should see a voltage rise from one and a voltage drop from the other.
 
Thank you for your reply. Does this mean I should have subtracted the second voltage(V2) in the equation of my big right loop?
 
It would appear that you're going around the loop clockwise (in the shown directions of I5 and I3, so that V2 would represent a voltage rise, while V1 would represent a voltage drop. That is,

V2 - V1 - I5*R5 - I3*R3 = 0
 
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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