Engineering Board Exam Reviewer · Thermodynamics · medium
For air with R = 0.287 kJ/kg· K and k = 1.4, what is the value of cp?
- 0.7175 kJ/kg· K
- 0.4018 kJ/kg· K
- 0.2050 kJ/kg· K
- 1.0045 kJ/kg· K
Answer
D. 1.0045 kJ/kg· K
Solution
cp = kR/(k - 1) = 1.4(0.287)/0.4 = 1.0045 kJ/kg· K. (cv = R/(k - 1) = 0.7175)
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