Chapter 6, Problem 6.29P

2. The gain in entropy during an isothermal process of 5 lb of air at 60°F is 0.462 Btu/*R. What is the work in Btu?

1 kg of water, T1 = 300 ° C, P1 = 200 kPa in a piston-cylinder assembly passes a process to its final state at constant pressure T2 = 150 ° C by throwing heat from its initial state to the surrounding environment. At the end of this process, determine(a) Piston boundary work, (b) The amount of heat discharged from the piston to the surrounding environment, (c) The amount of entropy produced by the piston cylinder (d) The amount of entropy produced by the surrounding environment. (Take the piston cylinder surface temperature 150 ° C!)

1 kg of water, T1 = 300 ° C, P1 = 200 kPa in a piston-cylinder assembly passes a process to its final state at constant pressure T2 = 150 ° C by throwing heat from its initial state to the surrounding environment. At the end of this process, determine (a) Piston boundary work, (b) The amount of heat discharged from the piston to the surrounding environment, (c) The amount of entropy produced by the piston cylinder (d) The amount of entropy produced by the surrounding environment. (Take the piston cylinder surface temperature 150 ° C!) witer ! ambient enviroņment 1 kg

The entropy change of a system can be negative, but the entropy generation cannot.

Water contained in a closed, rigid tank, initially at 100 lb;/in², 800°F, is cooled to a final state where the pressure is 50 lb;/in?. Determine the quality at the final state and the change in specific entropy, in Btu/lb-°R, for the process.

A steel casting (Ĉp = 0.12 kcal/kgK) weighing 40 kg and at a temperature of 500 ° C is quenched in 100 kg of oil (Ĉp=0.6 kcal/kgK) at 15 ° C. There are no heat losses, find (A)the entropy generated during the process (B) Lost work ? △Stotal=? kcal/K  W=? kcal

A piston-cylinder device contains 2 kg of water which is initially a saturated liquid at 300 ∘ C. It undergoes three processes to form a cycle. The first process is constant volume, the second is constant pressure at 2 bar and the third is a polytropic process where Pv 1.1 = constant. If you can calculate the heat transfer and work (both in kJ ) for each process. Is the device a heat engine or a refrigerator? Answer Table Description Work transfer for first process (kJ) Heat transfer for first process (kJ) Work transfer for second process (kJ) Heat transfer for second process (kJ) Work transfer for third process (kJ) Heat transfer for third process (kJ) Heat engine (1) or refrigerator (2) Value Value Thank you

1. thermodynamics

A divider separates 1 lb mass of carbon monoxide (CO) from a thermal reservoir at 150o F. the carbon monoxide, initially at 60o F  and 150 lbf/in2, expands isothermally to a final pressure of 10 lbf/in2 while receiving heat transfer through the divider from the reservoir. The carbon monoxide can be modeled as an ideal gas. (a) For the carbon monoxide as the system, evaluate the work and heat transfer, each in Btu and the amount of entropy produced, in Btu/oR. (b) Evaluate the entropy production, in Btu/oR, for an enlarged system that includesthe carbon monoxide and the divider, assuming the state of the divider remains unchanged. Compare with the entropy production of part (a) and comment on the difference.