A cylindrical tank of diameter D contains liquid to an initial height of h 0 . At time t = 0, a small stopper of diameter d is removed from the bottom. Assume Torricelli’s idealisation of efflux from...

A cylindrical tank of diameter D contains liquid to an initial height of h₀. At time t = 0, a small stopper of diameter d is removed from the bottom. Assume Torricelli’s idealisation of efflux from a hole in the bottom of the
 where h is the height of the free surface from the bottom of the tank. Determine the depth of liquid at time t. As a numerical example, assume diameter of the tank as 60 cm and that of the stopper as 6 mm. Initial height of the liquid is 0.5 m. Find the time required for the liquid height drop by 40 %.