Solved UPSC CDS/OTA Question
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Q · Work, Energy and PowerMedium · 45s
If a machine’s efficiency is 80% and input power is 500 W, its useful output power is:
TopicWork, Energy and Power
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.
Useful output = 80% of 500 W = 400 W.
Final Answer: Option A — 400 W