Engineering Board Exam Reviewer · Thermodynamics · hard
An ideal Otto cycle has an efficiency of 55%. What is its compression ratio? (k = 1.4)
- 16.36
- 2.22
- 4.46
- 7.36
Answer
D. 7.36
Solution
0.55 = 1 - 1/r0.4 r0.4 = 1/0.45 r = (2.222)2.5 = 7.36.
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