Circuit analysis in series vs. parallel

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The discussion focuses on determining whether resistors in a circuit are arranged in series or parallel. The user concludes that the resistors are neither in series nor in parallel due to unequal currents through the resistors and the mismatch of incoming and outgoing currents at junctions. They express uncertainty about applying Kirchhoff's rules and how to properly set up the electric potentials in the circuit. Guidance is provided on redrawing the circuit to clarify the nodes, which are confirmed to be the same as junction points. The conversation emphasizes the importance of understanding circuit configuration for accurate analysis.
daviddee305
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I need to determine whether the resistors on this circuit are in series or in parallel. Here's my reasoning...

They are not in series because the current going through each resistor is not equal: I1 \neq I4 \neq I5 *

*This is assuming I've assigned current properly which I'm not sure I have. Please tell me if there's a mistake in how I've split the current and how to correct it.

And they are not in parallel because the current flowing into each junction does not equal the current flowing out of each junction, because each junction splits into two currents.

I think I can show this algebraically using Kirchhoff's rules, but I don't how to set up each electric potential because I don't know where each loop begins or ends, or if this circuit even constitutes a loop and Kirchhoff's rules apply.

Please offer some guidance and help me understand how to analyze this properly. I really need to understand if these are in series or in parallel, and why.
 

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In the second drawing, notice that some of the nodes with different designations are actually the same node. Redraw the circuit again but this time draw it so the ends of the resistors that are on the same node are close to each other.
 
I don't know if 'nodes' are the same thing as 'junction points', but I think you're telling me to redraw the circuit like this... is this correct?
 

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Yes, nodes are the same as junction points and yes that is the way to redraw the circuit.
 
awesome, thanks for the help... I didn't know you could combine junction points like that... I was trying to make sense of it by manipulating the equations for kirchhoff's rules...
 
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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