Question

An interplanetary probe of volume 300 ft3 contains air at 14.7 psia and 77oF. The heaters fail and the air begins to cool. Assume heat is dissipated from the outside of the spacecraft by radiation at a steady rate of 60 Btu/h. On board electronics generate 12 W on average. Estimate the time required for the air to cool to –30oF.

Answer 1

Answer 2

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