Magnetic force between two wires

AI Thread Summary
The discussion centers on calculating the magnetic force between two wires carrying a high current of 468,055 amps at 1000 volts. The calculations yield a magnetic field strength of 9.36 tesla and a force of approximately 43,815 Newtons between the wires. Participants note that such high currents would likely cause the wires to vaporize under normal conditions. The conversation also touches on the implications of using superconducting wires, which would not follow Ohm's law and could still lead to damage from the voltage source's internal resistance. Overall, the calculations highlight the extreme energy levels involved in this scenario.
Danyon
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I'm wanting to know the force between two wires carrying current but I think I did something wrong when I calculated it. Here is my working.
I got a value of 0.0021365 ohms for both wires from http://chemandy.com/calculators/round-wire-resistance-calculator.htm
1000 volts pass through the wires. V=IR so I=V/R which is 1000/0.0021365 = 468055.2305 amps. Is this right?
Magnetic field strength at distance r, where r = 0.01 is B=μ0I/2πr, which is 4π*10^-7*468055.2305/2π*0.01
which equals 9.3611046 tesla. is this right?
Force between the wires is F=BIL where B is 9.3611046 tesla, I is 468055.2305 amps and L equals the length of wire = 0.01 this equals 43815.13971 Newtons. Is this correct? I've checked a few times on my calculator but I still don't believe how large the force is.
 
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I haven't checked your calculations, but the V=IR one is right.

You might want to consider just how much energy is involved in delivering 400,000+ amps at 1000 V... How does it compare with the output of a commercial power plant? You should expect to see some big numbers, although in practice your wires would vaporize the moment you turned the power on.
 
Nugatory said:
I haven't checked your calculations, but the V=IR one is right.

You might want to consider just how much energy is involved in delivering 400,000+ amps at 1000 V... How does it compare with the output of a commercial power plant? You should expect to see some big numbers, although in practice your wires would vaporize the moment you turned the power on.

Would the wire vaporise at 1000 volts if it where a superconducting wire?
 
If the wire is superconducting then it is not Ohmic and you can't use V = IR.

In reality, if you were to apply that voltage across a superconducting wire, you'd probably melt the voltage source as that still contributes its own internal resistance to the circuit.
 
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