Molecular Physics | Thermodynamics Answers

Steam at 2 MPa and 250°C in a rigid cylinder is cooled until the quality is 30%. Find the heat rejected from the cylinder.

@ 2 Mpa and 250°C: υ = 0.11144 m3 /kg

                   u = 2679.6 kJ/kg

 @ 2 Mpa, (saturated):υf = 0.0011767 m3 /kg

                    υg = 0.09963 m3 /kg 

                    uf = 906.44kJ/kg 

                    ug = 1693.8 kJ/kg

For a certain gas, R=0.277 kJ/kg.K and k=1.384. (a) What are the value of cp and cv? (b) what massof this gas would occupy a volume of 0.425 cu m at 517.11 kPa and 26.7°C? (c) if 31.65 kJ are transferred to this gas at constant volume in (b), what are the resulting temperature ans pressure?

A 2 kg oxygen execute an internally reversible process whereby heat is received, causing the total entropy to increase by 1.8 kJ/K for an initial temperature of 90oC. Determine the final temperature if the process is constant volume.

A 0.6 m3 tank contains gas at a pressure of 6800 kPa gage, a temperature of 75oC and mass of 25 kg. A part of this gas was discharged and the temperature and pressure changed to 60oC and 4130 kPa respectively. Heat was applied and the temperature was back to 75oC. Find the final mass, discharged mass, and the final pressure of the gas . 

 A container having a volume of 0.2 m3 contains Nitrogen at 100 kPa and 150C. If 0.2 kg of Nitrogen is pumped into this container, calculate the final pressure after the gas has returned to its initial temperature.

If 2.83 m3 of atmospheric air (101.3 kPa) at 0oC are compressed to a volume of 0.0283 m3 at a temperature of 76oC, what will be the pressure of the air in kPa.

The height of a cylindrical tank, containing 15 lb of gas at 70 psia and 115o F is triple its diameter; the gas constant R = 45 ft-lb/lboR. Find the tank height. 

What is the mass of the air contained in a room 6m X 5m x 4m if the pressure is 100 kPa and the temperature is 25oC

What is the angular velocity of an object traveling in a circle of radius 0.75 with a linear speed of 3.5m/s?

If you release the metal block, will it sink, or will it float to the surface? Explain.