I need to calculate the equivalent resistance

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SUMMARY

The discussion focuses on calculating the equivalent resistance between points A and B in a circuit diagram referenced as "Fig.4". Participants confirm that the initial assumption of a resistor being shorted is incorrect, clarifying that the wire connects to another resistor instead. The correct approach involves recognizing that nodes A and E are electrically the same, which simplifies the circuit analysis. Participants recommend renaming nodes and using color-coding for clarity in circuit representation.

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SaiTatter
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Homework Statement


The circuit is the one in "Fig.4"
dTMsA0n.jpg

I need to calculate equivalent resistance between A and B. This is what I've tried:
w0ZCnUq.jpg

I think that the first resistor is shorted by that wire connected between A and E. Their answer looks like this, in fig 2.2.1. I'm not sure if their answer is wrong, or my idea about electricity has flaws. Thanks in advance for the explanations!
jrpmShY.jpg
 

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Welcome to the PF. :smile:

Their answer/figure is correct. Just notice how point "A" connects to one side of those 3 R resistors, and the other side of each of those 3 R resistors are all connected together.
 
Thanks berkeman! So proud to be here :).
 
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Glad to help. :smile:
 
[QUOTE="SaiTatter]
I think that the first resistor is shorted by that wire connected between A and E.[/QUOTE]

That's not correct. The wire doesn't connect one side of the resistor to the other side. It connects it to another resistor.

Note that some nodes (eg A and E) are connected together by wire so they are really the same electrical node. Try renaming node E to node A. Likewise for any other nodes that have two names. It might help to colour the wires so points that are connected together are the same colour.

How many different nodes are there? The answer only has 3.

Then redraw the circuit starting with a line of these 3 nodes. Then add the resistors between them.
 

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