Avapor is compressed in a frictionless piston-cylinder such that the volume changes from 100 to 10 in3 . the initial pressure is 50 psia and temperature is held constant at 100°f. calculate the work in ft lbf. the vapor can be assumed to be an ideal gas.

Explanation:

The given data is as follows.

         Initial volume () = 100

         Final volume () = 10

         Initial pressure () = 50 psia = 50

          Temperature =

So, we assume that vapors are also ideal gas.

Hence, the work done for ideal gas will be calculated as follows.

                 W =

Since, it is given that the temperature is constant so, it is an isothermal process.

Therefore, work done for isothermal process is as follows.

                  W =

Putting the values into the above formula as follows.

                W =    

                     =

                     = -11512.925 lbf-in

As there are 12 inch present in 1 ft. So, converting lbf-in into lbf-ft as follows.

                W =

                     = -959.41 lbf-ft

The negative sign means work is supplied.

Thus, we can conclude that the work done is -959.41 lbf-ft.

i'm assuming that the correct answer is indeed the first one/ "a"..