Example Problems

Here are some example problems based on the material
in this lesson. I encourage you to read them,
think about them and maybe give them a try yourself. Then click on the
solution link at the end of each problem to see my solution and a good explanation.
Click on the Help Blog link to see questions and answers about each problem.

7B-1 :

Reversible Adiabatic Compression of R-134a

5 pts

A piston-and-cylinder device contains saturated R-134a vapor at -5°C. This vapor is compressed in an internally reversible, adiabatic process until the pressure is 1.0 MPa. Determine the work per kg of for this process.
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7B-2 :

Work Output of an Adiabatic, Reversible Turbine

5 pts

Steam enters an adiabatic turbine at 5 MPa and 450°C and leaves at a pressure of 1.4 MPa. Determine the work output of the turbine per kg of steam flowing through the turbine if the process is reversible and changes in kinetic and potential energies are negligible.
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7B-3 :

Entropy Change of an Isobaric Process

6 pts

Consider a process in which 1.00 kg of saturated water vapor at 100°C is condensed to a saturated liquid in an isobaric process by heat transfer to the surrounding air, which is at 25°C. What is the change in entropy of the water? What is the change in entropy of the surroundings? What is the change in the entropy of the universe?
Click here to see the complete solution , Help Blog
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  • Download Data Tables
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  • Homework problem hints and answers
  • Get Help from Dr. B in the LT Blog
  • 120 day membership

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  • Download Data Tables
  • Download Study Aids
  • Homework problem hints and answers
  • Get Help from Dr. B in the LT Blog
  • 120 day membership

Get it ALL for $5 US