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Wed 11 Jan, 2006 09:14 pm
I want to do an experiment/project and I will need to pump air into the bottom of a large container of water through a 1/2" tube. The container is a large trash bucket, about 4 ft tall and 3 ft diameter. I can either run the air hose over the top of the bucket to the bottom, or drill a hole at the bottom of the bucket for the hose and seal around it. I am seeking the method that would need the least amount of pressure to force the air to the bottom of the bucket. Would it be any easier to pump the air in if I run the hose up through the bottom of the bucket? I have already found that it takes a lot of force to pump it in from the top. Thanks.
If you put the hose at the same depth, it will take the same amount of pressure either way. The pressure required is directly related to the height of water over the exit point of the hose.
P=rho*g*h
Drilling a hole in the bottom will ruin a perfectly good trash can.
Rap
Thanks for the formula. However, since I have never taken a physics class, hopefully you will kind enough to help out on this question regarding the formula... Would it take twice as much force to pump air int a water-filled container that held twice as much water? And is it the water volume or the water height that effects the force needed to pump the air?
Thanks!
The force required is directly proportional to the height of water above the exit point of the hose. That's it. The volume doesn't matter.
Please forgive my ignorance, but does this formula mean that it takes 2X the force to pump air into 2X deep water, 3X for 3x, etc?
Thanks!
@Buffalo,
Hey,
Please answer me this question, Instructions to Add Air to a Water Pressure Tank by Tire Pump or a Compressed Air Source???
Thank you in advance.
@joyce19,
Instructions should have come with the ballast or pressure accumulator.