5. Consider a carton of milk that is refrigerated at a temperature of Tm = 5 °C. The kitchen temperature on a hot summer day is T- -30 °C. If the four sides of the carton are of height and width L 200 mm and w= 100 mm, respectively, determine the heat transferred to the milk carton as it sits on the kitchen counter for durations of t=10 s, 60 s, and 300 s before it is returned to the refrigerator. The convection coefficient associated with natural convection on the sides of the carton is h= 10 W/m²K. The surface emissivity is 0.90. Assume the milk carton temperature remains at 5 °C during the process. Your parents have taught you the importance of refrigerating certain foods from the food safety perspective. Comment on the importance of quickly returning the milk carton to the refrigerator from an energy conservation point of view.

Q: 2. The initial temperature of the hot coffee cup is T(0) = 175°F. The cup is placed in a room…

A: *

Q: = How long should it take to boil an egg? Model the egg as a sphere with radius of 2.3 cm that has…

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Q: The temperature at the inner and outer surfaces of a boiler wall made of 25 mm thick steel and…

A: solutiongiven dataTi=350°CT∘=600°Cb1=25 mmb2=15 mmks=68 w/m°CKins=0.126 w/m°C

Q: Q5 Two large containers A and B of the same size are filled with different fluids. The fluids in…

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Q: passes across the blades of the fan some of the heat energy of this steam is transferred into the…

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Work and Heat Transfer

It is generally related to thermal engineering which tells about the use, creation, conversion and transfer of heat energy between the systems. It is also considered that to transfer heat from one source to another, transfer of masses is also required. There are various mechanisms by which, transfer of heat takes place i.e. thermal conduction, convection, radiation or by change of phase. All these mechanisms have their own specific features which sometimes occur simultaneously within the same system.