A particular steel beam is able to survive 25,000 cycles of a cyclic stress of 150 MPa (alternating from tension to compression) and is able to survive 10,000 cycles of a cyclic stress of 200 MPa (alternating from tension to compression). If that beam is subjected to 15,000 cycles of stress of 150 MPa (alternating from tension to compression), how many additional cycles of stress of 200 MPa (alternating from tension to compression) can it withstand before breaking

Acommercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -35°c by rejecting waste heat to cooling water that enters the condenser at 18°c at a rate of 0.25 kg/s and leaves at 26°c. the refrigerant enters the condenser at 1.2 mpa and 50°c. if the compressor consumes 3.3 kw of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load, (c) the cop, and (d) the minimum power input to the compressor for the same refrigeration load.