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Author Topic: why can't you use water instead of mercury in a mercury barometer?  (Read 4420 times)

Offline mcjhn

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



 

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
 

Offline mcjhn

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brilliant thanks a lot!

I was puzzling over that for a while
 

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 »
 

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