Of the following, which is the best description of the second law of t

1.	Of the following, which is the best description of the second law of thermodynamics?
Answer» The total energy of the UNIVERSE is a constant. The efficiency of a heat engine can never be greater than 50 percent. The amount of heat required to vaporise a liquid is greater than the amount of heat required to melt a solid of the same substance. The entropy of the universe is always increasing. Solution :Choice (A) is the first law of thermodynamics. CHOICES (C) and (D) are true, but they are not EQUIVALENT to the second law of thermodynamics. Choice (B) is FALSE, but if it read, "The efficiency of a heat engine can never be equal to 100 percent", then it would be equivalent to the second law.

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Of the following, which is the best description of the second law of thermodynamics?

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