Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: mcjhn on 29/09/2010 00:27:23

Title: Why do barometers use mercury rather than water?
Post by: mcjhn on 29/09/2010 00:27:23

Can you use water instead of mercury in a barometer? If not, why not?

Title: Re: Why do barometers use mercury rather than water?
Post by: Geezer on 29/09/2010 00:35:10

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]

Title: Re: Why do barometers use mercury rather than water?
Post by: mcjhn on 29/09/2010 00:43:07

brilliant thanks a lot!

I was puzzling over that for a while

Title: Re: Why do barometers use mercury rather than water?
Post by: syhprum on 29/09/2010 07:10:24

Another problem is that water puts out much more vapour than Mercury and contaminates the vacuum at the top making the device temperature sensitive.