What volume of air is needed to float 800 lbs of cargo above water?

Im building a pontoon/catamaran %26amp; i need to know how much air needs to be contained under the boat.


Also, are there any simple equations to figure this out?What volume of air is needed to float 800 lbs of cargo above water?
800 lb = 363 kg of mass





density of water is 998 kg/m鲁





363 kg / 998 kg/m鲁 = 0.364 m鲁


so a volume of 0.364 m鲁 of water will support 363 kg of load. For an accurate number, we have to subtract the weight of the same volume of air.





Density of Air 1.28 kg/m鲁


1.28 kg/m鲁 x 0.364 m鲁 = 0.46 kg, too small to matter.





Answer is 0.364 m鲁 or 12.9 ft鲁





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