Q.

A vessel wih square cross-section and height of 6 m is vertically partitioned. A small window of 100 cm2 with hinged door is fitted at a depth of 3 m in the partition wall. One part of the vessel is filled completely with water and the other side is filled with the liquid having density 1.5×103 kg/m3. What force one needs to apply on the hinged door so that it does not get opened (Acceleration due to gravity = 10 m/s2)          [2025]


Ans.

(150)

in equilibrium

Fext+Fw=Fl

 Fext=FlFw

                     =(P0+ρlgh)A(P0+ρwgh)A

                      =(ρlρw)ghA

                      =(15001000)×10×3×(100×104)

                      = 150 N.