Water Stands At A Depth Of 15m Behind A Reservoir Dam. A Horizontal Pipe 4 Cm In Diameter Passes Through The Dam 6m Below The Surface Of Water As Shown. There Is Plug Which Secures The Pipe Opening. Then The Friction Between The Plug And Pipe Wall Is:

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Water stands at a depth of 15m behind a reservoir dam. A horizontal pipe 4 cm in diameter passes through the dam 6m below the surface of water as shown. There is plug which secures the pipe opening. Then the friction between the plug and pipe wall is:


Correct option is

74 N


As plug secures the pipe opening, the force of friction between plug and pipe wall.


But p1 = p0 and      

                 p2 = p0 + hg






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