A volume of air (assumed to be an ideal gas) is first cooled without charging its volume and then expanded without changing its pressure, as shown by the path abc in Figure 15.35. (a) How does the final temperature of the gas compare with its initial temperature? (b) How much heat does the air exchange with its surroundings during the process abc? Does the air absorb heat or release heat during this process? Explain. (c) If the air instead expands from state a to state c by the straight-line path shown, how much heat does it exchange with its surroundings?
Figure 15.35
Problem 52.
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