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Old 25 January 2011, 10:41   #11
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Torkin bollix

If you hit a particularly big wave and took off in to outer space then you would have 16psi in them

or am I torkin bollix
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Old 25 January 2011, 10:41   #12
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I think its all down to Boyle's Law, which according to Wikipedia says -

Boyle’s law states that at constant temperature for a fixed mass, the absolute pressure and the volume of a gas are inversely proportional. The law can also be stated in a slightly different manner, that the product of absolute pressure and volume is always constant.

So if you reduce the temperature the volume reduces as well.

We all get floppy tubes in the cold weather!
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Old 25 January 2011, 10:46   #13
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Torkin bollix

If you hit a particularly big wave and took off in to outer space then you would have 16psi in them

or am I torkin bollix
yep you're torkin bollox, the air is colder and not ambient or am i still torkin bollox
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Old 25 January 2011, 10:59   #14
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yep you're torkin bollox, the air is colder and not ambient or am i still torkin bollox
I was thinking along the lines of there's no atmosphere in space so your tube pressure would go up by 1 atmosphere (relative to the atmosphere outside the toob. I might just shut up now before I make a complete fool of myself
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Old 25 January 2011, 11:21   #15
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yep you're torkin bollox, the air is colder and not ambient or am i still torkin bollox
Ambient simply means the surrounding "normal" environment. Ambient on a hot day may be 90 degrees F; on a cold day, 30 degrees F.

Ambient temp in the space example is kind of moot, as there's no gas to measure a temp from. The temps recorded by astronauts are usually read off other surfaces.

jky
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Old 25 January 2011, 11:29   #16
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What about air pressure rather than just temp?

900mb is 13psi

1000mb is 14.5psi

Also bear in mind that the temperature of the air inside the tubes will go up like the seats of a locked car, no air moving in or out to adjust it so pretty warm inside on a sunny day.
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Old 25 January 2011, 11:51   #17
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i think......










we've all got too much time on our hands
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Old 25 January 2011, 12:24   #18
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What about air pressure rather than just temp?

900mb is 13psi

1000mb is 14.5psi

Also bear in mind that the temperature of the air inside the tubes will go up like the seats of a locked car, no air moving in or out to adjust it so pretty warm inside on a sunny day.
Indeed - but also a few drops of water will make a big difference to pressure fluctuations if condensing/evaporating.
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Old 25 January 2011, 12:34   #19
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Indeed - but also a few drops of water will make a big difference to pressure fluctuations if condensing/evaporating.
You should see the effect of a few drops of homebrew on pressure fluctuations!
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Old 25 January 2011, 12:36   #20
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If you can't understand why your tubes go up and down due to a fluctuation in air temp then I suggest you have a look on here: http://www.boatmad.com/forum/
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