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Question 31097
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Kinetic Theory and Thermodynamics: Entropy Advanced MCQ

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Entropy AdvancedHardQuestion 31097

Question

Maxwell's demon thought experiment failed because:
  1. A
    Demons are too slow
  2. B
    Observing/erasing information about molecules requires energy (Landauer's principle)
    Correct
  3. C
    Temperature fluctuations prevent it
  4. D
    Quantum mechanics forbids it

Correct answer

Observing/erasing information about molecules requires energy (Landauer's principle)

Explanation

Landauer (1961): erasure of one bit of information requires minimum k ln2 of energy dissipated as heat, compensating the entropy decrease the demon creates.

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