A tank of square cross-section of each side is filled with a liquid of height h . Find the thrust experienced by the vertical surfaces and bottom surface of the tank.

Explanation

Over the verticla surface, the pressure due to liquid is not same at all point . The points at Greater depth experience large pressure and hence greater thrust. Average pressure on the vertical surface of tank in contact with liquid.
`P_(av) = ((0+h rhog))/(2) = 1/2 h rho g`
`:.` Thrust on the vertical surfaces of tank
`P_(av) xx area = ((h rho g)/(2)) xx 4 hl = 2 glh^(2)`
Over the bottom surface, the pressure due to liquid is uniform at all points which is given by. `P=h rho g`
`:.` Thurst on the bottom surface = `P xx l^(2)`
`= h rho g l^(2)`.