Condition of Equilibrium of a Floating Body

Two equal but opposite forces act on a floating body – One is the weight of the body which acts downwards and another is the buoyancy of the liquid which acts in the upward direction. To keep the floating body in equilibrium, these two forces must act along the same straight line. Otherwise, these two forces will constitute a couple and will produce a rotational motion in the body. Hence, for the equilibrium of a floating body, the following two conditions must be satisfied.

Condition of Floatation:

The weight of the floating body must be equal to the weight of the liquid displaced by the body.

Condition of Equilibrium:

The center of gravity of the body and the center of buoyancy must lie on the same vertical line.