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What heat flow cannot occur spontaneously under the second law?

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  1. From hot to cold
  2. Across a metal wall
  3. From cold to hot

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References

  1. OpenStax University Physics Volume 2, Reversible and Irreversible Processes openstax.org/books/university-physics-volume-2/pages/4-1-reversible-and-irreversible-processes Checked 2026-10-10.

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