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General Science / Re: What happens when a superconductor is utilised in a circuit?
« on: 08/01/2024 09:15:39 »Quote from: jasonlava
Closing the switch should mean no current flows, thanks to the infinite time constant of the superconductor.If we assume the inductance is around 100nH (for a circuit with length 4 inches), and the inductance is the main impediment to current flow...
The current can be described as V=L dI/dt
- Where V is the applied voltage. We'll use 1V DC in this example
- L is the inductance in Henries (but we will use 100nH in this example = 10-7 H)
- I is the current flowing through the circuit
- dI/dt is the rate of increase of current with time, in Amps per Second.
So V=L dI/dt
1 = 10-7 dI/dt
or dI/dt = 107 Amps/second = 10 million Amps after 1 second, which is a huge amount of current!
This is enough to turn most thin superconductors into normal conductors, due to exceeding the critical current.
So the assumption that "no current flows" is a fallacy.