The uniform slender bar of mass m and length l is released from rest in the vertical position and pivots on its square end about the corner at O. (a) If the bar is observed to slip when find the coefficient of static friction between the bar and the corner. (b) If the end of the bar is notched so that it cannot slip, find the angle at

Arefrigerator uses r-134a as the working fluid and operates on the ideal vapor-compression refrigeration cycle except for the compression process. the refrigerant enters the evaporator at 120 kpa with a quality of 34 percent and leaves the compressor at 70°c. if the compressor consumes 450 w of power, determine (a) the mass flow rate of the refrigerant, (b) the condenser pressure, and (c) the cop of the refrigerator. (0.00644 kg/s, 800 kpa, 2.03)