Cooled air is flowing through a long, sheet metal air conditioning duct 0.2 m high and 0.3 m wide. If the duct temperature is and passes through a crawl space under a house at , estimate (a) the heat...

Cooled air is flowing through a long, sheet metal air

conditioning duct 0.2 m high and 0.3 m wide. If the duct

temperature is and passes through a crawl space

under a house at , estimate (a) the heat transfer rate

to the cooled air per meter length of duct and (b) the

additional air conditioning load if the duct is 20 m long.

(c) Discuss qualitatively the energy conservation that

would result if the duct were insulated with glass wool.