During a steady flow process, the pressure of the working substance drops from 200 to 20 psia, the speed increases from 200 to 1000 fps, the internal energy of the open system decreases to 25 Btu/lb, and the specific volume increases from 1 to 8 ft/lb. No heat is transferred. Sketch an energy diagram. Determine the work per lb. Is it done on or by the substance? Determine the work in hp for 10 lb/min. Note that 1 hp 42.4 Btu/min. =