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Kirchhoff’s junction rule is based on conservation of charge and the outgoing currents add up and are equal to incoming current at a junction.

but Bending or reorienting the wire does not change the validity of Kirchhoff’s junction rule. how it is possible?

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    $\begingroup$ Why do you think it would? $\endgroup$ – Bob D Sep 2 at 14:46
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The physical basis of KCL is that charge doesn't build up in any region of the wire. And since charge is a conserved quantity that means that for any volume of space within your circuit, the algebraic sum of currents through the surface of that volume must be zero.

Since none of the physical assumptions behind KCL depend on the specific arrangement or shape of the wires, changing the arrangement or shape of the wires doesn't invalidate the law.

But, the pre-condition that charge doesn't build up in any region of the wire isn't a truth of nature. It's an approximation (part of the lumped circuit approximation) that limits the type of circuits where KCL is actually valid. If this approximation weren't valid for some particular circuit, we just wouldn't use KCL to analyze it.

In a physical circuit bending the wires might change the parasitic capacitance between one wire (for example, one that's inside the test volume) and another one (outside the volume). Then there would be some charge build up in the two capacitively coupled wires. To apply KCL in this case we must represent the parasitic capacitance with a capacitor element in our circuit model, and keep track of the current through it as one of the currents that contributes to the inward or outward current of the nodes it connects to.

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Why it will change. it is like coming charge or electrons equals to going electrons on junction,if you disorient it will have no effect on those electrons , as long as you don't touch two conducting wires. Imagine you have a extension board and you are just moving wires connecting devices to it.i know it is not ideal example , but it'll work i think.

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  • $\begingroup$ I don't get your extension board example $\endgroup$ – Garima Singh Sep 2 at 15:21

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