For heat transfer calculations, a vertical cylinder 180 cm tall and 30 cm in diameter is used to represent a human. The cylinder is placed in a large room where the air temperature is 20°C and the wall temperature is 10°C. Assume that the surface temperature of the cylinder is 25°C, the convective heat transfer coefficient h = 12 W/m2·°C, and the surface emissivity is ε = 0.9. Calculate the rate of heat lost from the cylinder.

For heat transfer calculations, a vertical cylinder 180 cm tall and 30 cm in diameter is used to represent a human. The cylinder is placed in a large room where the air temperature is 20°C and the wall temperature is 10°C. Assume that the surface temperature of the cylinder is 25°C, the convective heat transfer coefficient h = 12 W/m2·°C, and the surface emissivity is ε = 0.9. Calculate the rate of heat lost from the cylinder.

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