If I have a resistance wire, twice the surface area and length, vs another wire with half the surface area and length,
Would they result in the same amount of Johnson noise or would the bigger wire have more?
The equation does not include geometrical properties, which is why I'm curious. Since this noise comes from electrons vibrating, wouldn't a bigger longer resistor generate more of this noise?
Edit: Might have posted in wrong section, mods please help move thanks.
Would they result in the same amount of Johnson noise or would the bigger wire have more?
The equation does not include geometrical properties, which is why I'm curious. Since this noise comes from electrons vibrating, wouldn't a bigger longer resistor generate more of this noise?
Edit: Might have posted in wrong section, mods please help move thanks.
Providing the resistance were the same, the Johnson noise I think would be the same.
That doesn't however take into account other properties of the wire such as the different self inductance between the two which again (I think 🙂)would modify the result.
Remember you are talking of purely theoretical... Johnson noise proportional to resistance... which is an "absolute", and then "modifying" that with "real" wire that is anything but purely resistive.
Interesting question.
That doesn't however take into account other properties of the wire such as the different self inductance between the two which again (I think 🙂)would modify the result.
Remember you are talking of purely theoretical... Johnson noise proportional to resistance... which is an "absolute", and then "modifying" that with "real" wire that is anything but purely resistive.
Interesting question.
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