Water at 58C is being used to cool apples from an initial temperature of 208 to 88C. The water flow over the surface of the apple creates a convective heat-transfer coefficient of 10 W/(m2 K). Assume the apple can be described as a sphere with an 8-cm diameter and the geometric center is to be reduced to 88C. The apple properties include thermal conductivity of 0.4 W/(m K), specific heat of 3.8 kJ/(kg K), 3 and density of 960 kg/m . Determine the time that the apples must be exposed to the water.

Machinery that is a key part of the process and without which the plant or process cannot function is classifed as: (clo4) a)-critical machinery b)-essential machinery c)-general purpose machinery d)-none of the specified options.

Avolume of 2.65 m3 of air in a rigid, insulated container fitted with a paddle wheel is initially at 264 k, 5.6 bar. the air receives 432 kj by work from the paddle wheel. assuming the ideal gas model with cv = 0.71 kj/kg • k, determine for the air the amount of entropy produced, in kj/k

Refrigerant-134a enters the compressor of a refrigerator as superheated vapor at 0.14 mpa and -10°c at a rate of 0.05 ka/s and leaves at 0.8 mpa and 50°c. the refrigerant is cooied in the condenser to 0.72 mpa and 26'c. it is then throttled to 0.15 mpa. sketch the t-s diagram for the system and evaluate: 6) the rate of heat removai from the refrigerated space (kw), it) the power input to the compressor (kw), ii) the isentropic efficiency of the compressor (%), and iv) the cop of the refrigerator.