In
fluid mechanics, displacement occurs when an object is immersed in a
fluid, pushing it out of the way and taking its place, so that it can be weighed.An object that sinks also displaces an amount of fluid equal to the object's
volume. Thus
buoyancy is expressed by
Archimedes' Principle which states that when this happens, the
weight of the object is reduced by its volume times the
density of the fluid. If the weight of the object is less than this quantity, it will float, if more it will sink. The amount of fluid displaced is directly related (via Archimedes' Principle) to its weight.
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