A substance contained in a flexible, well-insulated containerundergoes an expansion process from an initial state with aspecific volume of 10 ft3 /lb and pressure of 12 lbf/in2 to a finalstate with a specific volume of 24 ft3 /lb. During the process, thesubstance’s pressure varies according to Equation 1 where pi is thesubstance’s initial pressure and vi is the substance’s initialspecific volume. The substance’s internal energy decreases by 500Btu during the process. Neglect potential and kinetic energychanges.
a. Determine the specific work done on the substance inBtu/lb.
b. Determine the mass of the substance in lb.
? = (??/ 2) â‹… (1 + (??/?) )
