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Very Basic Circuit Q

  • Thread starter User1265
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Homework Statement
Image insert.
Are the two resistors in series or Parallel? and why so?
Homework Equations
V=IR
2019-10-07.png
 

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kuruman

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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.
 
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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
 
Last edited:
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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
 
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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.
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.
 

kuruman

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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".
"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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