Q1) A rod consisting of two cylindrical portions AB and BC is restrained at both ends. Portion AB is made of steel (Es= 200 GPa, αs= 11.7 x 10-6

/°C) and portion BC

of brass (Eb= 105 GPa, αb= 20.9 x 10-6

/°C). Knowing that the rod is initially

unstressed, determine,

a) the reactions at A and B by a temperature rise of 55°C.

b) the normal stresses induced in portions AB and BC by a temperature rise of

55°C.

An electrical motor raises a 50kg load at a construct velencity .calculate the power of the motor, if it takes 40sec to raise the load through a height of 24m(take g =9.8n/g)

Refrigerant 134a enters an insulated compressor operating at steady state as saturated vapor at -26°c with a volumetric flow rate of 0.18 m3/s. refrigerant exits at 9 bar, 70°c. changes in kinetic and potential energy from inlet to exit can be ignored. determine the volumetric flow rate at the exit, in m3/s, and the compressor power, in kw.

For the closed feedwater heater below, feedwater enters state 3 at a pressure of 2000 psia and temperature of 420 °f at a rate of ix10 ibhr. the feedwat extracted steam enters state 1 at a pressure of 1000 psia and enthalpy of 1500 btu/lbm. the extracted er leaves at an enthalpy of 528.7 btu/lbm steam leaves as a saturated liquid. (16) a) determine the mass flow rate of the extraction steam used to heat the feedwater (10) b) determine the terminal temperature difference of the closed feedwater heater