Physics-
General
Easy
Question
An intense stream of water of cross-sectional area
strikes a wall at an angle
with the normal to the wall and returns back elastically. If the density of water is
and its velocity is
,then the force exerted in the wall will be

The correct answer is: 
Linear momentum of water striking per second to the wall
, similarly linear momentum of reflected water per second 

Now making components of momentum along
- axes and
-axes. Change in momentum of water per second


By definition of force, force exerted on the Wall 
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