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Criticism of Feynman’s analysis of the ratchet as an engine
Abstract
The well-known discussion on an engine consisting of a ratchet and a pawl in [R. P. Feynman, R. B. Leighton, and M. Sands, The Feynman Lectures on Physics (Addison-Wesley, Reading, MA, 1963), Vol. 1, pp. 46.1–46.9] is shown to contain some misguided aspects: Since the engine is simultaneously in contact with reservoirs at different temperatures, it can never work in a reversible way. As a consequence, the engine can never achieve the efficiency of a Carnot cycle, not even in the limit of zero power (infinitely slow motion), in contradiction with the conclusion reached in the Lectures.
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Citations
Cited by
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Virtual qubits, virtual temperatures, and the foundations of thermodynamics
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Metadata
- Authors
- Parrondo, J. M. R., & Español, P.
- Venue
- American Journal of Physics
- Published
- 1996-09-01
- Volume
- 64
- Issue
- 9
- Pages
- 1125-1130
- ISSN
- 0002-9505 (ISSN-L)
- 1943-2909
- OpenAlex
- W1975264154
- Cited by
- 203
- References
- 0
- FWCI
- 5.42
- Type
- journal article
- Language
- en
- Open access
- closed
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