Electrical – Two short circuits

conductorsresistanceshort-circuit

enter image description here

I wanted to ask a concept but couldn't guess how to explain so I'm taking help from this example. This is not a homework problem.

Now my doubt is all the current will go through the horizontal perfect conducting wire (short circuit) then travel upwards and will encounter another perfect conducter with no resistance.

So will it travel through it or just ignore it? If it does will it not be trapped in a loop? I need only the concept and reason for it not the solution.

schematic

simulate this circuit – Schematic created using CircuitLab

CircuitLab version for the OP to use for figuring out.

Best Answer

The concept of a short circuit commonly trips people up at first. There is actually no short circuit in the schematic you've posted.

It may help to consider every line as an infinitely flexible rubber band, that joins points in the circuit that are all the same. So the junction between R1 and R2, and R7 and R8 are actually the same point, electrically. The fact there's a line between and they're on the opposite sides of the schematic is just a matter of the way it is drawn.

So the challenge in understanding these circuits is to realise what is connected to what (regardless of how it's drawn).

If you want to imagine current travelling through the circuit (which is not a bad strategy), then imagine current has left node A and passes through R1. It then splits and follows all paths from there - some goes to R2, some goes to R7 and some (possibly negative) to R8. What the split is depends on the overall circuit, and which paths appear to be lower resistance. When you work it out, you'll find there are no loops and no short circuits.

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