Thermodynamics

A piston and cylinder machine containing a fluid system has a stirring device in the cylinder the piston is frictionless, and is held down against the fluid due to the atmospheric pressure of 101.325kPa the stirring device is turned 10,000 revolutions with an average torque against the fluid of 1.275MN. Mean while the piston of 0.6m diameter moves out 0.8m. Find the net work transfer for the systems.

Assume we have a refrigerator operating at steady state using 500 W of electric power with a COP of 2.5. What is the net effect on the kitchen air?

A steel cylinder of mass 2 kg contains 4 L of liquid water at 25°C at 200 kPa. Find the total mass and volume of the system. List two extensive and three intensive properties of the water 

Make a control volume that includes the steam flow around in the main turbine loop in the nuclear propulsion system in Identify mass flows (hot or cold) and energy transfers that enter or leave the C.V.

A heat transfer requires a temperature difference, see chapter 4, to push the Q.. What implications do that have for a real heat engine? A refrigerator?

A windmill produces power on a shaft taking kinetic energy out of the wind. Is it a heat engine? Is it a perpetual machine? Explain. 

When is the reversible work the same as the isentropic work? 

Which of the following equations represent standard heat of formation of methane

The shaft work in a pump to increase the pressure is small compared to the shaft work in an air compressor for the same pressure increase. Why?  

Water at 100 kPa, 150°C receives 75 kJ/kg in a reversible process by heat transfer. Which process changes s the most: constant T, constant v or constant P?

ds = dq/T