A water tank of constant depth H open to the atmosphere is c
     A water tank of constant depth H, open to the atmosphere, is connected to the piping system shown in the figure below. After a length of pipe L of diameter D, the diameter decreases smoothly to a value of D/2 and then continues on for another length L before exiting to atmosphere. The friction factor/is the same for all piping. C_D1 and C_D2 are the loss coefficients for the entry and exit. Calculate the depth of the tank required to produce an exit velocity of V.   
  
  Solution
The answer of the following question is as follows .
The required depth of thetank tO produce the exit velocity is D4/6

