1. A person is standing in a room maintained at 20 degrees of C at all...

1. A person is standing in a room maintained at 20 degrees of C at all times. The inner surfaces of the walls, floors, and the ceiling of the house are observed to be at an average temperature of 10 degrees C in winter and 25 degrees C in summer. Determine the rate of radiation heat transfer between this person and the surrounding surfaces if the exposed surface area and the average outer surface temperature of the person are 1.5 m^2 and 29 degrees C respectfully. The emissivity of human skin at these wavelengths/temperatures is 0.95. Now, If the person above were in a breezy room, how much additional energy would be lost via convection? The convection heat transfer coefficient is 6 W/m^2 K? (b) What percentage of the total is this? (Calculate this for summer and for winter.)

Expert Solution

genius_generous answered 2 years ago

Question 2 (b) Consider a person standing in a breezy room at 20°C. Determine the total...

Question 2 (b) Consider a person standing in a breezy room at 20°C. Determine the total rate of heat transfer from this person if the exposed surface area and the average outer surface temperature of the person are 1.6 m2 and 29°C, respectively, and the convection heat transfer coefficient is 6 W/m2 • °C. (c) A specific strength of materials is very high when they are in fiber size but lower when they are in bar form - Why?

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