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What is the maximum theoretical efficiency possible for an engine operating between 100°C and 400°C?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter22: Entropy And The Second Law Of Thermodynamics

Section: Chapter Questions

Problem 3PQ: Use a PV diagram such as the one in Figure 22.2 (page 653) to figure out how you could modify an...

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A 2.00-mol sample of a diatomic ideal gas expands slowly and adiabatically from a pressure of 5.00 atm and a volume of 12.0 L to a final volume of 30.0 L. (a) What is the final pressure of the gas? (b) What are the initial and final temperatures? Find (c) Q, (d) Eint, and (e) W for the gas during this process.
Figure P21.45 shows a cyclic process ABCDA for 1.00 mol of an ideal gas. The gas is initially at Pi = 1.50 105 Pa, Vi = 1.00 103 m3 (point A in Fig. P21.45). a. What is the net work done on the gas during the cycle? b. What is the net amount of energy added by heat to this gas during the cycle? FIGURE P21.45
Use a PV diagram such as the one in Figure 22.2 (page 653) to figure out how you could modify an engine to increase the work done.
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