Breathing from a 30ft. snorkel

[Serdin]

The answer to this questions has nothing to do with the ambient pressure. The answer is "Resistance". The longer the hose, the more resistance builds up. Take a 3 foot garden hose and breath through it, the a 5 foot, 10 foot and so on. The longer the hose, the hard to breath. There is friction between the air and the inside of the hose, the more friction, the more resistance thus harder to breath.

 

[Cave Diver]

The answer to this questions has nothing to do with the ambient pressure. The answer is "Resistance". The longer the hose, the more resistance builds up. Take a 3 foot garden hose and breath through it, the a 5 foot, 10 foot and so on. The longer the hose, the hard to breath. There is friction between the air and the inside of the hose, the more friction, the more resistance thus harder to breath.

So you're saying that if I can breathe through a 5' piece of garden hose while standing on the ground I should be able to breathe through same said piece of hose while lying on the bottom of a pool? Because in either case, all I have to do is overcome the friction?

 

[Serdin]

Yes, However, a hose may compress with the pressure. However, if you took a rigid piece of PVC pipe that wont compress, I believe it would be the same as if on the surface.

 

[Cave Diver]

Yes, However, a hose may compress with the pressure. However, if you took a rigid piece of PVC pipe that wont compress, I believe it would be the same as if on the surface.

Ok. So I can take a 10' piece of rigid PVC. Stand on the surface and breathe through it, even hold it straight up and down. If I then walk into the water with it til there is only 1' sticking above the surface I will still be able to breathe?

Have you tried this? Can you validate this claim?

 

[mooney]

The answer to this questions has nothing to do with the ambient pressure. The answer is "Resistance". The longer the hose, the more resistance builds up. Take a 3 foot garden hose and breath through it, the a 5 foot, 10 foot and so on. The longer the hose, the hard to breath. There is friction between the air and the inside of the hose, the more friction, the more resistance thus harder to breath.

Yes, However, a hose may compress with the pressure. However, if you took a rigid piece of PVC pipe that wont compress, I believe it would be the same as if on the surface.

negativeto the first one...
And negative to the second. Just looked it up in my old NASDS book. It is under the subject "breathing tubes." Breathiing tubes/snorkels are rigid, like the PVC, and it clearly states that any breathing tube over about a foot long will be impossible to breathe from due to increased ambient pressure on the lungs, as others have said. Not friction.

 

[vondo]

Let him see if he can drink a bottle of coke through a 33 INCH long straw.

EDIT: I posted ft but the equivalent of 1 ATM is 33 inches of water.

No, an atmosphere is 33 ft. of water. But I imagine a 33 inch straw is still beyond the capabilities of most people.

 

[tregrrr]

serdin ... stop

go read your open water manual again ... Before you go in back the water

Cave Diver ... play nice I know its not often that lambs walk in and fall asleep beside the wolves in the wolf den....

 

[Cave Diver]

No, an atmosphere is 33 ft. of water. But I imagine a 33 inch straw is still beyond the capabilities of most people.

I guess this crazy straw is out.

 

[Cave Diver]

serdin ... stop

go read your open water manual again ... Before you go in back the water

Cave Diver ... play nice I know its not often that lambs walk in and fall asleep beside the wolves in the wolf den....

Hey! I am playing nice. I just wanna make sure I understand the claim correctly!

 

[Cave Diver]

I am curious about 33" straw now though.