This calculator was created at a user's request. He wanted to find the weight of a body in liquid. So, here comes the Archimedes' principle: The buoyant force on a submerged object is equal to the weight of the liquid displaced by the object.
So, from one side, the body in the liquid is affected by the gravity force, which is or . From the other side, the body in the liquid is affected by the buoyant force. Now, everything depends on the body's density. If it is greater than the liquid density, the body will sink, if not – it will be pushed out of the liquid until the two forces become equal (The buoyant force becomes less as the body comes up out of the liquid). The part in the water will be proportional to the liquid/body densities ratio.
The difference between actual weight and apparent weight will be equal to the weight of the liquid that was displaced, and it is the volume of the body under the water multiplied by liquid density.