Question 2.1: During testing, compressed air from a cylinder is used to in......

Engineering Thermodynamics [1393131]

During testing, compressed air from a cylinder is used to inflate an inelastic flexible fire hose, originally folded completely flat, to a volume 0.48 m³. If the barometer reads 749 mm Hg, what is the amount of work done upon the atmosphere by the fire hose?

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The displacement work,

$W = W_{cyl}+ W_{hose} = 0 + \int{pdV_{hose}} = \frac{749}{760} \times 101.325 \times 0.48 = 47.93 kJ$

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