A Carnot heat engine receives heat from a reservoir at 900degreeC at a rate of 800 kJ/min and rejects the waste heat to the ambient air at 27degreeC. The entire work output of the heat engine is used to drive a refrigerator that removes heat from the refrigerated space at -5degreeC and transfers it to the same ambient air at 27degreeC. Determine the maximum rate of heat removal from the refrigerated space and the total rate of heat rejection to the ambient air. Answers, 4982 kJ/min. 5782 kJ/min

Tom is having a problem with his washing machine. he notices that the machine vibrates violently at a frequency of 1500 rpm due to an unknown rotating unbalance. the machine is mounted on 4 springs each having a stiffness of 10 kn/m. tom wishes to add an undamped vibration absorber attached by a spring under the machine the machine working frequency ranges between 800 rpm to 2000 rpm and its total mass while loaded is assumed to be 80 kg. a) what should be the mass of the absorber added to the machine so that the natural frequency falls outside the working range? b) after a first trial of an absorber using a mass of 35 kg, the amplitude of the oscillation was found to be 10 cm. what is the value of the rotating unbalance? c) using me-3.5 kg.m, find the optimal absorber (by minimizing its mass). what would be the amplitude of the oscillation of the absorber?