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Gustav Kirchhoff (1824-1887) was an accomplished Prussian physicist and instrument maker, and best known for his current and voltage circuit laws. Kirchhoff’s first circuit law, known as his current law, states that the algebraic sum of currents in a network of conductors meeting at a point is zero. Kirchhoff’s second circuit law, known as his voltage law, states that the sum of the voltages, taking into account their polarities, in a closed circuit is zero.

Kirchhoff’s current law is based on conservation of charge, measured in coulombs, which is current integrated over (multiplied by) time. SPICE and similar circuit simulation software make use of a matrix version of Kirchhoff’s current law along with Ohm’s law to perform nodal analysis of more complex circuits. So you would think that at this point, there is little that is controversial about Kirchhoff’s laws. That brings us to a series of YouTube videos that, surprisingly, explore the idea that Kirchhoff’s laws might not hold under certain circumstances.

>Gustav Kirchhoff (1824-1887) was an accomplished Prussian physicist and instrument maker, and best known for his current and voltage circuit laws. Kirchhoff’s first circuit law, known as his current law, states that the algebraic sum of currents in a network of conductors meeting at a point is zero. Kirchhoff’s second circuit law, known as his voltage law, states that the sum of the voltages, taking into account their polarities, in a closed circuit is zero. >Kirchhoff’s current law is based on conservation of charge, measured in coulombs, which is current integrated over (multiplied by) time. SPICE and similar circuit simulation software make use of a matrix version of Kirchhoff’s current law along with Ohm’s law to perform nodal analysis of more complex circuits. So you would think that at this point, there is little that is controversial about Kirchhoff’s laws. That brings us to a series of YouTube videos that, surprisingly, explore the idea that Kirchhoff’s laws might not hold under certain circumstances.

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[–] • 2 pts

sigh

First off, you can't induce a current in a straight wire compared to a coil. A coil to coil works, as does a straight wire to a straight wire. Induction works between parallel wires. The section of wire where the current is being induced is essentially turned into an active component, like that battery. Its being drawn as a stright line is a distraction to keep you from thinking it's an active component. Its being a superconductor is beside the point and is being added as a distracting complication. And while current can loop forever in a superconductor, add resistors and it will quickly cease, the power dissipated.

[–] [deleted] • 1 pt

The section of wire where the current is being induced is essentially turned into an active component, like that battery. Its being drawn as a stright line is a distraction to keep you from thinking it's an active component.

Agreed.

[–] • 1 pt

My vocational school electronics instructor, a guy that had been in electronics as long as there had been electronics to be in (1980s at the time) always said "Call it Kirch-off and not Kirk-off, because I don't want to hear you talking about jerkoff's law."

We still called it jerkoff's law.