Pressure gauge submerged in a fluid column

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TyErd
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Homework Statement


What reading will we see on a pressure gauge that is at the middle and bottom of a fluid column? and why


Homework Equations


P=pgh where p is density and P is pressure


The Attempt at a Solution


Well according to the equations as the gauge drop lower and lower it should decrease in pressure meaning before the gauge is dropped in it must have a greater than zero reading on the gauge and as it descends it reduces until it reaches zero, however that cannot be the case because pressure will increase when an object is submerged under water. Does it have something to do with buoyancy?
 
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so that means the readings will be opposite? so the gauge pressure at the top will be zero since h is zero?
 
TyErd said:
so that means the readings will be opposite? so the gauge pressure at the top will be zero since h is zero?

The equation gives the pressure at the bottom of a column, given the columns height. To use this equation, we simply define the gauge position as the bottom of the column. (We know that the fluid below the gauge does not affect its reading).