Theoretically, shouldn't there be no current flowing through a short circuit? Across the short circuit, the voltage is 0, and the resistance is ideally 0 as well. So how does it make sense for any current to pass through?
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Theoretically, the answer is no. Here is a way to visualize it:
Start off with a voltage source of $V$ volts connected to a resistance of $R$ ohms. This establishes a current $I = V/R$ amperes through the resistor.
Now cut the resistance in half. The current now is $I = V/(R/2)$ or $2V/R$, twice what it was before.
Do this again: Now you've cut the resistance by a factor of four, and in response the current goes up by a factor of four.
So in the limit of resistance $R$ going to ~(very small), the current $I$ goes to ~(very large). In theory, making $R$ zero drives the current to infinity, but in the real world there are no power supplies that can source infinite current. A real-world power supply facing a very low load resistance will fail to maintain constant voltage and will instead sag down as the load resistance goes to zero.
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niels nielsen
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A current does not necessarily have to have an electric field to drive it. F.e. in a vacuum electrons can move according to Newton's law without the need of an electric field. Only for the start of the move a force is needed. Or a gravitational field may be the driving force. In a closed loop superconductor (shortcut), electrons are circling endlessly. For symmetrical reason, if there was any electric field between 2 points in a homogenous superconductor loop, the electrons would travel in direction of the positive field gradient and also in the opposite direction = negative field gradient, thus compensating any energy transfer. But a perfect conductor is anyway free of a static electric field. Once the electrons are accelerated in a superconductor via a magnetic field, no field is needed to run the electrons in infinite number of circles.
