Solving Node Voltage: Va = Vb x R1/(R1+R0)

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The discussion focuses on solving for node voltage using the equation Va = Vb x R1/(R1+R0). A user expresses confusion over the calculation of Vb, questioning why the equivalent resistance of 4 ohms in parallel is used instead of just the 2-ohm resistor directly in front of Vb. Another participant clarifies that the total resistance on the right side of the circuit is indeed 2 ohms, resulting from the series combination of two 2-ohm resistors. They suggest that understanding the equivalent resistance simplifies the analysis and leads to determining that the voltage drops across these resistors are equal. The conversation emphasizes the importance of correctly analyzing circuit components to find node voltages.
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Homework Statement


Find the node voltage


Homework Equations



Va = Vb x R1/(R1+R0)

The Attempt at a Solution



I didnt have the original picture of the question but this example is exactly same as the question that i had to solve. but I don't understand this thing from the first step.
How can Vb = Va x (4//4)/(4//4+2)? I know that the 2ohms at the right side of circuit can be added as series and functions as 4ohm and it is paralle to 4 ohm in the middle. and so the total resistance of the circuit is 4//4 +2, but why do we use 4//4 to find Vb? isn't it just 2ohm in front of Vb that we have to use?
Help please
Thanks
 

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What does the symbol // (as in 4 // 4) mean?
 
There are a lot of ways to analyze circuits and its been alittle while for me. That being said the easiest way to find Vb would be to find the resultant resistance of the right hand side/loop of the circuit. Since it turns out to be equal to 2 ohms then you have two resistors in series that are both 2 ohms. Thus the voltage drops will be equal to each other and be 1/2 of the source voltage or 3 volts.
 
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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