why can't you use water instead of mercury in a mercury barometer?

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Offline mcjhn

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can you use water instead of mercury in a barometer like this? if not, why?


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Offline Geezer

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You are in luck. You can! However, because water is a lot less dense than mercury, the water column has to be about 30 feet tall  [;D]
There ain'ta no sanity clause, and there ain'ta no centrifugal force Šther.

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Offline mcjhn

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brilliant thanks a lot!

I was puzzling over that for a while

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Offline syhprum

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Another problem is that water puts out much more vapour than Mercury and contaminates the vacuum at the top making the device temperature sensitive.
« Last Edit: 29/09/2010 13:06:19 by syhprum »
syhprum