Engineering Board Exam Reviewer · Thermodynamics · medium
In an air-standard Otto cycle, the temperature after compression is 700 K and after heat addition is 1800 K. What is the heat added per kg? (cv = 0.718 kJ/kg· K)
- 789.8 kJ/kg
- 1105.5 kJ/kg
- 315.7 kJ/kg
- 1292.4 kJ/kg
Answer
A. 789.8 kJ/kg
Solution
Constant-volume heat addition: q = cv(T3 - T2) = 0.718(1100) = 789.8 kJ/kg.
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