4. Steam enters an adiabatic turbine at 900 psia and 900F and leaves at a pressure of 50 psia. Determine the maximum amount of work that can be delivered by this turbine.

 

w_max =305 Btu/lbm

 

6. 1-kg of air at 3500 kPa and 127C is contained in a piston-cylinder device. Air is now allowed to expand in a reversible, isothermal process until its pressure is 1200 kPa. Determine the amount of heat transferred to the air during this expansion.

 

Q_in = 123 kJ

7. Steam at 300 psia and 700F is expanded adiabatically in a closed system to 10 psia. Determine the work produced, in Btu/lbm, and the final temperature of steam for an isentropic expansion efficiency of 80 percent.

w = 193 Btu/lbm, T2 = 193 ^oF