In a lead-shot tower, spherical 0.95-cm-diameter BB shots are formed by drops of molten lead which solidify as they descend in cooler air. At the terminal velocity, i.e., when the drag equals the gravitational force, estimate the total heat transfer coefficient if the lead surface is at 171?C, the surface of the lead has an emissivity of 0.63, and the air temperature is 16?C. Assume CD = 0.75 for the first trial calculation.GIVENSpherical lead-shot falling through the air at terminal velocityShot diameter (D) = 0.95 cm = 0.0095 mLead surface temperature (Ts) = 171?C = 494 KLead surface emissivity (ε) = 0.63Air temperature (T??) = 16?C 289 KAssume CD = 0.75 for the first trial calculationASSUMPTIONSThe surroundings act as a black body enclosure atT|??

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D-0.95 cm Alr T,-171°C T.= 16°C U.