The time required to cool the truck from
Answer to Problem 142RP
The time required to cool the truck from
Explanation of Solution
Determine the mass of the air in the truck.
Here, the density of air is
Determine the amount of heat removed from the truck.
Here, the specific heat at the average temperature is
Determine the average temperature in the truck during precooling.
Determine the average rate of heat gain by transmission.
Here, the rate of transmission heat gain occurs is
Determine the time required to cool the truck.
Conclusion:
From the Table A-2, “Ideal-gas specific heats of various common gases” to obtain value of density of air and the specific heat at the average temperature of
Substitute
Substitute 116 kg for
Substitute
Substitute
Substitute 2320 kJ for
Thus, the time required to cool the truck from
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Chapter 6 Solutions
THERMODYNAMICS
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