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UPSC Combined Geo-Scientist

Chemist

  • 2 objective papers
  • 120 questions each
  • 2 h per paper
  • 100 + 300 marks

Prelims Paper II covers chemistry.

UPSC Combined Geo-Scientist, Prelims · 2026 · Paper II, Chemistry · Q57 of 120

Geo-Scientist Prelims 2026 Chemistry Q57: Suppose the coldest reservoir we have at hand is at 12°C. If we…

QuestionThermodynamics / Carnot efficiency

Suppose the coldest reservoir we have at hand is at 12°C. If we want a heat engine that is at least 90% efficient, the minimum temperature of the required hot reservoir should be

  1. (a) 2577 K
  2. (b) 2577°C
  3. (c) 100°C
  4. (d) 373 K

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