Brownian Ratchet (exercise framed by Feynman's Lectures, l. 46)

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SUMMARY

The discussion centers on the analysis of a Brownian ratchet device, originally proposed by Smoluchowski and quantitatively analyzed by Feynman. The device consists of a paddle and a ratchet, both immersed in ideal gases at different temperatures, ##T_1## and ##T_2##. When ##T_1 > T_2##, the system can achieve a net angular velocity, while at equilibrium (##T_1 = T_2##), it exhibits no net rotation due to the random motion of the pawl. Key calculations involve the average force exerted by gas molecules, the viscous drag coefficient, and the energy transferred during the ratchet's rotation.

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  • #31
I now have another new favorite Feynman chapter.......he does his version of the fluctuation-dissipation theorem in 46-2 of this lecture. I think it probably not too different from the original sources Einstein-Smoluchowslki.
 
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  • #32
Hak said:
Ok, thanks, I'll try the simpler case first. I will submit my result shortly.
I'm looking forward to it.
 
  • #33
bob012345 said:
I'm looking forward to it.
I am working on it, between tomorrow and the day after tomorrow I will publish my process. Thanks.
 
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