Question 1. For a body completely submerged in a fluid, the centre of gravity (G) and centre of Buoyancy (0) are known. The body is considered to be in stable equilibrium if [2011 : 1 Mark]
(a) O does not coincide with the centre of mass of the displaced fluid
(b) G coincides with the centre of mass of the displaced fluid
(c) O lies below G
(d) O lies above G
Solution: A completely submerged body will be in stable equilibrium when CG lies below the centre of buoyancy. It will be in unstable equilibrium when CG lies above the centre of buoyancy. And when the CG coincides with the centre of buoyancy, the body will be in neutral equilibrium.