Circuit Q Basics: Understand Electrical Circuits

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The discussion centers on understanding electrical circuits, specifically the behavior of resistors in series and parallel configurations. Kirchhoff's current law is highlighted, stating that the sum of currents into a node equals the sum flowing out. A key point is that a short circuit (0 ohm resistor) connected to a 6 ohm resistor results in all current flowing through the short, leaving the 6 ohm resistor with no current. Participants express confusion about the instructions regarding current flow and equivalent resistance calculations. Ultimately, it is clarified that the current will always choose the path of least resistance, which is the short circuit in this scenario.
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Homework Statement
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Are the two resistors in series or Parallel? and why so?
Relevant Equations
V=IR
2019-10-07.png
 

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As per our Forum rules you must make an effort to answer the question before you can receive help. Tell us what you think.
 
Recall Kirchhoff's current law, the sum of currents flowing into a node is equal to the sum of currents flowing out of it. Two resistors are said to be in series if they are siege to the same current, otherwise they are parallel.
Your circuit is a bit special, however. The wire connecting the two poles of the ##6\,\Omega## resistor short-circuits it because it is considered to be a ##0\,\Omega## resistor, as a result of which we theoretically assume that all the current will pass through it and none will pass through the bottom resistor. You might ask why this is, and I'll answer : compute the equivalent resistance with ##R_1=6\,\Omega## and ##R_2=0\,\Omega## and you'll find it to be ##0\,\Omega##.
2019-10-07.png
 
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"compute the equivalent resistance with ##R_1=6\,\Omega## and ##R_2=0\,\Omega## and you'll find it to be ##0\,\Omega##."

Thank you! I forgot the zero resistance, but I don't understand the instructions quoted above, explaining as to why no current will pass though the 6 ohm resistor
 
kuruman said:
As per our Forum rules you must make an effort to answer the question before you can receive help. Tell us what you think.
I thought 6 ohm and 4 ohm were parallel since they shared the same two nodes, but I'm not sure if this is even the correct reason, as there is a battery between in the upper branch opposite the diagonal branch.
 
User1265 said:
I thought 6 ohm and 4 ohm were parallel since they shared the same two nodes, but I'm not sure if this is even the correct reason, as there is a battery between in the upper branch opposite the diagonal branch.
For future reference, something like this belongs in your original post under "Attempt at a solution".
User1265 said:
"compute the equivalent resistance with ##R_1=6\,\Omega## and ##R_2=0\,\Omega## and you'll find it to be ##0\,\Omega##."

Thank you! I forgot the zero resistance, but I don't understand the instructions quoted above, explaining as to why no current will pass though the 6 ohm resistor
The 6 ohm resistor is in parallel with the short (0 ohm resistor). When the current reaches the node, it will take the path of least resistance. In this case all the available current will go through the short.
 
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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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