The instantaneous liquid displacement is . It is of interest to determine the manner in which increases from zero initially to a final value of . Let be the cross-sectional area of the tube and be the length of the liquid column. The energy equation for the column is written as
Here the total energy of the manometer liquid consists of kinetic and potential energies and is written as
. It is of interest to determine the manner in which 
increases from zero initially to a final value of 
. Let 
be the cross-sectional area of the tube and 
be the length of the liquid column. The energy equation for the column is written as 
