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Old 11th May 2010 | 13:24
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Dont Hang Up
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Joined: Mar 2008
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From: Malvern, UK
Sorry but the good old Oxford Dictionary has it correct.

A siphon will not work in a vacuum. Yes gravity provides the motive force, but the lift requires ambient pressure to push the liquid upwards (against gravity).

No ambient pressure - no lift - no siphon.

Rudderrudderrat is quite correct with a maximum lift (for water) around 35 feet at sea level. At FL350 it would be less than 10 feet. And in a vaccum it would be zero.

If you can't get past "the water would boil" issue then think of doing it with mercury instead. But then the lift is less by a factor of about 10 (but still zero in a vacuum).

Last edited by Dont Hang Up; 11th May 2010 at 14:22.
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