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enter image description hereI have to calculate the current and equivalent resistance but I don't even understand where to start. I'm not looking for a straight out answer I just want to know how I should go about solving it?

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    \$\begingroup\$ The first step for these esoteric circuits, I find, is to redraw the schematic to understand the series/parallel connections more easily. (Hint - are there actually any series connections in this circuit?) \$\endgroup\$ Commented Nov 2, 2021 at 12:56
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    \$\begingroup\$ I’m voting to close this question because it appears to be homework with no attempt to solve it. \$\endgroup\$
    – Null
    Commented Nov 2, 2021 at 12:58
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    \$\begingroup\$ That circuit does not need circuit analysis. It is a trick question. It is just drawn deliberately against best practices to look like it is difficult to confuse people. Nobody would ever draw a simple four resistor circuit like that in real life. Just look at how the battery connects to each resistor. \$\endgroup\$
    – Justme
    Commented Nov 2, 2021 at 13:02
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    \$\begingroup\$ @AdamLawrence Are they all in parallel to eachother because theyre connected corner to corner? \$\endgroup\$ Commented Nov 2, 2021 at 13:04
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    \$\begingroup\$ I voted to reopen because the OP specifically stated that they were looking for guidance on how to start, not an answer to the problem as presented. @Oisin Although this is an acceptable format homework question, the community here (myself included) often has what might be described as a violent allergic reaction to homework questions because they very often consist of pasting the published question with no explanation of where the author is stuck or what they've tried. \$\endgroup\$
    – JYelton
    Commented Nov 2, 2021 at 14:59

4 Answers 4

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Oooh, that looks nasty.

The first thing I would do in your shoes is to try and draw the same circuit in planar form, where no wires cross. It's not always possible, but it can be done here:

schematic

simulate this circuit – Schematic created using CircuitLab

Then move things around until you find something you recognise. In this case it's quite easy, but I admit at first I thought I saw a notoriously confusing bridge arrangement in there, which might require some "wye-delta" transformations. I was wrong, thankfully. Here's my attempt to find something I can deal with:

schematic

simulate this circuit

Clearly R2 and R4 are in parallel, as are R1 and R3. You could stop shuffling here, but there's more. If you look closely, R3 and R4 are also in parallel, as are R1 and R2!

I won't give you any more hints, because I'm sure you know where to go from here, but I will say this: even after decades in the game, I still often have to redraw schematics to make them make sense to me. I like to have currents flow from top to bottom, with high potentials at the top and low potentials at the bottom. I like to have signals flow left to right, with inputs on the left, and outputs on the right. I like circuits to be as planar as possible, crossed wires are always confusing. If I can't do this in my head, which is very often, I am not afraid to redraw it on paper, so that it doesn't confuse me any more, and neither should you be.

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  • \$\begingroup\$ Thank you very much the redrawing step makes that a lot easier to understand. \$\endgroup\$ Commented Nov 2, 2021 at 13:52
  • \$\begingroup\$ It isn't a bridge or anything advanced. Any attempt to redraw this which doesn't result in 4 resistors between + and ground in parallel needs more work. "Pull up to ground" isn't a thing - ground is never upwards in schematics or something is wrong. \$\endgroup\$
    – Lundin
    Commented Nov 4, 2021 at 15:03
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This circuit is deliberately drawn as it is to disguise the fact that it is actually quite simple. Take a red pen or marker and trace the wire connected from the positive side of the 24V to the resistors; do the same with a different color for the negative side. This should help clear up the confusion

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  • \$\begingroup\$ Thank you, I have done that and the marker never went along the lines going from corner to corner. Is this correct? \$\endgroup\$ Commented Nov 2, 2021 at 13:37
  • \$\begingroup\$ @OisinO'Neill, user28910 didn't say that you couldn't lift the marker to start drawing a new line. Those diagonal lines do connect to the 24V battery's terminals - so trace them with the marker too. \$\endgroup\$
    – brhans
    Commented Nov 2, 2021 at 13:46
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This is what has been suggested in the comments and answers:

enter image description here

All resistors are connected between the same two nodes.

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All R's are sharing V+ V- logically in parallel , regardless of how it looks.

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