Oxygen is compressed from an initial state of p1 = 1 bar, T1 = 25◦ C to a final state of p2 = 650 kPa, T2 = 270◦C in a compressor operating at steady state. Model the oxygen as a perfect gas with γ = 1.4 and cp = 0.92 kJ/kg·K. Neglecting stray heat transfer and kinetic and potential energy effects, determine: (a) the work, in kJ per kg of oxygen flowing through the compressor. (b) the isentropic efficiency η for the compressor.

Adouble-strand no. 60 roller chain is used to transmit power between a 13-tooth driving sprocket rotating at 300 rev/min and a 52-tooth driven sprocket. a) what is the allowable horsepower of this drive? b) estimate the center-to-center distance if the chain length is 82 pitches. c) estimate the torque and bending force on the driving shaft by the chain if the actual horsepower transmitted is 30 percent less than the corrected (allowable) power.