4-4 Helium is compressed in a piston-cylinder device. The initial and final temperatures of helium and the work
required to compress it are to be determined.
Assumptions The process is quasi-equilibrium.
Properties The gas constant of helium is R = 2.0769
5-4C No, a flow with the same volume flow rate at the inlet and the exit is not necessarily steady (unless the density
is constant). To be steady, the mass flow rate through the device must remain constant.
5-7 Air is accelerated in a nozzle. The mass flo
There is no truth to his claim. It violates the second law of thermodynamics.
During an analysis, a relation with inconsistent units is obtained. A correction is to be found, and
the probable cause of the error is to be determ
College of Engineering & Computer Science
Department of Mechanical Engineering
MEC 320 Thermodynamics 1
Homework # 2A
Dr. Hamdi Sheibani
1 Chapter 3:
3-20C Ice can be made by evacuating the air in a water tank. During evacuation, vapor is also
thrown out, and thus the vapor pressure in the tank drops, causing a difference between the
vapor pressures at the water surface and in the tank. Th
Using hydropower to
lift a load
What is hydropower ?
The water cycle occurs when water evaporates from bodies
of water on Earth, like oceans, and thencondensesinto clouds.
Eventually, the clouds become too heavy and the water
returns to Earth in the form
Exergy: A Measure of Work Potential
Thermodynamics: An Engineering Approach, 7th edition
by Yunus A. engel and Michael A. Boles
Examining the performance of engineering devices based on the
second law of thermodynamics.