Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Heat and ThermodynamicsMedium · 45s
Which of the following is an irreversible process?
TopicHeat and Thermodynamics
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Spontaneous mixing cannot be reversed.
Final Answer: Option C — Mixing hot and cold water