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Re: emf, potential, voltage

At 09:53 AM 3/18/01 -0600, brian whatcott wrote:
A resistor is a resistor when it is hot.
....
an oscilloscope shows the noise emf satisfactorily.

I wish I had an oscilloscope as nice as Brian's.

Let us assume
R = 1 meg
BW = 200 MHz

When I do the calculations, it seems
-- a cool (300K) resistor has 0.91 mV RMS thermal noise, while
-- a hot (400K) resistor has 1.05 mV RMS thermal noise.

It takes a verrry fine oscilloscope to see that ... rather better than your
garden-variety classroom scope.