A thin flat plate 6 in. square is tested for drag in a wind tunnel with air at 100 fps, 14.7 psia, and 60?F flowing across and parallel to the top and bottom surfaces. The observed total drag force is 0.0135 lb. Using the definition of friction coefficient, Equation (4.13), and the Reynolds analogy, calculate the rate of heat transfer from this plate when the surface temperature is maintained at 250?F.GIVENAir flow over the top and bottom of a thin platePlate dimensions = 6 in. ×6 in. = 0.5 ft × 0.5 ftAir speed (U??) = 100 ft/sAir pressure = 14.7 psia = 1 atmAir temperature (T??) = 60?FTotal drag force (D) = 0.0135 lbSurface temperature (Ts) = 250?FASSUMPTIONSSteady stateConstant and uniform plate temperatureRadiation isnegligible

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Alr U.= 100 ft/s T-250°F Te = 60°C L=0.5 ft