Two identical cylindrical vessels are kept on the ground and each contain the same liquid of density
d. The area of the base of both vessels is S but the height of liquid in one vessel is x1
and in the
other, x2
. When both cylinders are connected through a pipe of negligible volume very close to the
bottom, the liquid flows from one vessel to the other until it comes to equilibrium at a new height.
The change in energy of the system in the process is: