Home › Previous year questions › GATE 2021 PI › Question 33GATE 2021 PI – Question 33 General Engineering · Thermal and Fluids Engineering · 1 mark · Numerical answer
An ideal Otto cycle receives 800 kJ/kg during constant-volume heat addition and rejects 381 kJ/kg during constant-volume cooling. Find thermal efficiency in % to one decimal.
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Show answer and explanation Correct answer: 52.2 to 52.5
Explanation Net work = 800−381 = 419 kJ/kg. Efficiency = 419/800 × 100 = 52.375%, rounding to **52.4%**.
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