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I am trying to find the current I1 at a specific point in the circuit below, but I am not sure what the best method would be to find it.

schematic

simulate this circuit – Schematic created using CircuitLab

I was thinking of manipulating the resistors and trying to use current divider, but I get confused on which resistors are in series and which are in parallel with each other. Is there a better way? Thanks

Edit: I think this is what the circuit looks like redrawn. Is this done correctly?

schematic

simulate this circuit

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    \$\begingroup\$ This is a very simple homework-type question. Please show us what you have tried so far. \$\endgroup\$ – Dwayne Reid Aug 26 '16 at 5:40
  • \$\begingroup\$ Well I was going to add R3 and R4 because I thought they were in series To make R34. Then that was parallel with R2 so i was going to end up with R234 in parallel with R1. I could then use the current divider formula to find I1. The problem I have is that when the circuit is laid out like this it isn't easy for me to tell what is in series and what is in parallel \$\endgroup\$ – oodan123 Aug 26 '16 at 5:47
  • \$\begingroup\$ Well then redraw it so that it is easy to tell what's in series and in parallel. Post a second schematic and you will get help. \$\endgroup\$ – Transistor Aug 26 '16 at 6:12
  • \$\begingroup\$ Schematics - more people will respond warmly to your schematics if they follow two simple style rules, stimulus on the left with conceptual flow going right, and ground or negative at the bottom with vertical current flow in components. Compare your diagram with Helloworld922's. It's the difference between getting into a hire car and finding the pedals the same as yours, or different. 99% of engineers will look at your diagram, and the first thing they have to do is translate it into something that looks right. HW922's looks right. \$\endgroup\$ – Neil_UK Aug 26 '16 at 7:10
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Step 1 is almost always re-drawing the circuit so it is easy to tell what is happening. Prove to yourself that the circuit you have is equivalent to this one below, and the answer should become obvious for what I1 should be.

schematic

simulate this circuit – Schematic created using CircuitLab

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  • \$\begingroup\$ Yeah thanks for that. My redraw was the same so now ill use two current dividers to find I1. \$\endgroup\$ – oodan123 Aug 26 '16 at 6:32
  • \$\begingroup\$ @oodan123 no, the connectivity of the diagram is the same, it represents the same circuit, but the diagram is different. \$\endgroup\$ – Neil_UK Aug 26 '16 at 7:13

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