Engineering, 12.07.2019 20:30 Kzamor

A1.27 cm diameter copper sphere is heated in an convection furnace for a very long time, so that its temperature becomes equal to the temperature (t=260c) of the air in the furnace. then, the sphere is removed from the furnace and is placed in a forced convection flow where the heat transfer coefficient h=17 w/(m^2-°c) and where the temperature is 38 oc. the sphere is allowed to remain in the flow for 7.5 minutes, at which time it is returned to the convection furnace. after 15 minutes in the furnace, the temperature of the sphere is 240.5 °c. find: (a) what is the temperature of the sphere just before it is returned to the furnace? (b) what is the convective heat transfer coefficient of the furnace?

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A1.27 cm diameter copper sphere is heated in an convection furnace for a very long time, so that its...

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