Archimedes' principle states that any body completely or partially submerged in a fluid at rest experiences an upward, or buoyant, force equal to the weight of the fluid it displaces. This physical law of buoyancy was discovered by the ancient Greek mathematician Archimedes, supposedly while he was taking a bath.
Archimedes'principle has several applications, one of which is to determine density and specific gravity. The principle also explains why objects float. If the weight of displaced liquid equals the weight of an object, it floats. If the displaced liquid weighs less than the object, the object sinks. When an object weighs less than the fluid it displaces, such as a heliumfilled balloon, it rises.
He proved that a body plunged in a fluid becomes lighter by an amount equal in weight to the amount of fluid it displaces.
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The buoyant force acting on an object is equal to the weight of the fluid
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1. Choose a depth of 1 foot for the bottom end of the imaginary cylinder. 2. Calculate the pressure for a depth of 1 foot of water. 1 cubic inch of water weighs 0.036 pounds, and
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Stuff that's less dense than water floats. Eg ice, or a boat. Bits of a boat (eg the metal) are more dense, but its average density is lower because there's lots of air in it. Stuff
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