I would like to ask a question which is partially addressed in this question:
Current in Parallel Circuits
Since the voltage in parallel is constant, why is it that when there is a short circuit, no current flows through the second path? Shouldn't the current in that path be independent of the other short circuit path?
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2 Answers
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If you have an ideal short circuit whose resistance is zero there can be no voltage across the short circuit otherwise an infinite (impossible) current will flow. So if there is no voltage across the short circuit then there is no voltage across the other parallel component and so no current will flow through that component. But note that since we already know that we put a nonzero voltage across the circuit, this conclusion is not really meaningful because we already have a contradiction.
What we can conclude is that there is no ideal short circuit. In fact, you are correct in thinking that a current will flow through he parallel component, as a short circuit in real life has a finite resistance. Of course, that current would be much smaller than the current through the (non-ideal) short circuit.
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There will of course be current flowing in the non-short-circuit path, so I'm not sure where you got the claim that there would be none. Anyway, there is also no such thing as a true short-circuit (zero-resistance) path.
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$\begingroup$ Even with superconductivity, putting a voltage across it will result in a non-equilibrium state with the temperature rising until it stops being a superconductor. The classical laws for electrical circuits only apply for equilibrium states, and we could say there's no true stable short-circuit. $\endgroup$ Commented Mar 6, 2016 at 9:46