An athlete is working out in the weight room. he steadily holds 50 kg above his head for ten seconds which statement is true about this situation.1 the athlete isn't doing any work because he doesn't move the weight.2 the athlete isn't doing any work because he doesn't hold the weight long enough. 3 the athlete is doing work because he prevents the weight from falling down.4 the athlete is doing work because 50 kg is a significant load to lift.

Ain is , is 's of ? 0.62 0.79 1.27 1.50

What is the single most important equation in all of physics?

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.