I need to calculate the equivalent resistance

[SaiTatter]

Homework Statement

The circuit is the one in "Fig.4"

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

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!

 

[berkeman]

Welcome to the PF.

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.

 

[SaiTatter]

Thanks berkeman! So proud to be here :).

 

[berkeman]

Glad to help.

 

[CWatters]

[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.