[عاطف خليفة]

Equilibrium Postulate


An isolated system in equilibrium is equally likely to be in any of its accessible states


Mechanical Equilibrium

A system is said to be in mechanical equilibrium if

where is the applied force and is the virtual displacement


Floating


Homogeneous spheres float stably in all possible orientations (Ulam 1960), but it has never been proved that no other homogeneous body shares this property (Gilbert 1991).

When the two above shapes have uniform density 0.5 they, like the uniform sphere of density 1, will float in a liquid in any orientation without tending to rotate (Mauldin 1982, Wells 1991, Gilbert 1991