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A flat wall is exposed to an environmental temperature of 38 degrees C. The wall is...

A flat wall is exposed to an environmental temperature of 38 degrees C. The wall is covered with a layer of insulation 2.5 cm thick whose thermal conductivity is 1.8 W/(m.K), and the temperature of the wall on the inside of the insulation is 320 degrees C. The wall loses heat to the environment by convection. Compute the value of the convection heat transfer coefficient that must be maintained on the outer surface of the insulation to ensure that the outer surface temperature does not exceed 40 degrees C.

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