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The effects of diameter changes to a manometer.

  1. May 21, 2013 #1
    How does the diameter change from one manometer say of radius x cm to say 2x or 3x cm change the height difference if the liquid in the manometer is of constant mass, density and gravitational field strength remains the same?

    P.S could some working also be shown just to get a mathematical insight.
    Reply asap please! :D
  2. jcsd
  3. May 21, 2013 #2


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    The pressure at the bottom of a column is not dependent upon the diameter of the tube (except when it is so narrow that capillary action becomes significant). What counts is the density of the liquid and the vertical distance to the surface (and g, of course).

    The difference between the levels of liquid in a manometer will be the same, whatever gauge of tube you use - even if one side is different from the other.

    This link is a bit 'noddy' but the various pictures show what I mean.
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