Q7 of 81 Page 273

Find the force exerted by the water on a 2 m2 plane surface of a large stone placed at the bottom of a sea 500 m deep. Does the force depend on the orientation of the surface?

Here, we first find the pressure at depth of 500m of water. We know the density of water, .


Pressure,


Given, area,


So the force, (ANS)


The force only depends on the depth of the water and the cross-sectional area of the stone and is same at all points lying in the same horizontal plane. So the force is independent of the orientation of the surface.


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