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what is artificial buoyancy?
Buoyancy is the ability of an object to float in a liquid.
A Greek mathematician named Archimedes determined why things float 2000 years ago. He established that "Any object wholly or partly immersed in a fluid is buoyed upby a force equal to the weight of the fluid displaced by theobject.". This explains why a steel ship floats, but its anchordoes not. The more water displaced, the greater the BUOYANCY.
If the weight of the displaced water (total displacement) is greater than the weight of the submerged body, the buoyancy is positiveand the object floats. If theweight of the displaced water is less than the weight of the object, then the buoyancy is negative and the object sinks.If the weight of the object is equal to the weight of the displaced water, then buoyancy is neutral and the object is suspended. Neutral buoyancy is the state frequently used when diving.

Buoyancy is dependent upon the density of the surrounding liquid. Seawater has a density of 64.0 pounds per cubic foot, compared to 62.4 pounds per cubic foot for freshwater. Therefore, each cubic foot of seawater that is displaced by a volume of air in a container has a liftingforce of 64 pounds. The greater the density, the greater the buoyancy force. Thus, it is easier to float in seawater thanin a freshwater lake.
An understanding of buoyancy serves the diver in a number of ways. By using weights, by expanding the air in a buoyancy compensator, or by increasing the size of a variable-volume diving suit, a diver can manipulate his buoyancy to meet operational needs. When working on the bottom, for example, a slightly negative buoyancy provides better traction and more stability on the sea
floor. Buoyancy is also an invaluable aid to lifting heavy items in salvage operations

 Diving with Self Contained Underwater Breathing Apparatus (SCUBA) equipment essentially demands the ability to maintain a constant depth in order to maneuver and work. Constantly adjusting buoyancy robs a scuba diver of much needed stamina and diverts attention from the objective of the dive, thereby taking away much of the diver’s pleasure and/or usefulness.

Through these and other realizations, he established what came to be known as the Archimedes Principle: An object in fluid is buoyed up by a force equal to the weight of the fluid the object displaces. Positive, Negative, and Neutral Buoyancy An object that floats in a liquid is positively buoyant. This means that the amount of water displaced by the object weighs more than the object itself.


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