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Bernoulli's Principle describes the relationship between the speed of a fluid and its pressure. Specifically, it states that in a streamline flow, an increase in the velocity of a fluid results in a decrease in its pressure or potential energy. This principle is fundamental in fluid mechanics and is derived from the conservation of energy, which indicates that the total mechanical energy of the flowing fluid remains constant.

In practical terms, this principle helps explain various phenomena, such as why an airplane wing generates lift or how a carburetor works in an engine. When air flows over the curved surface of a wing, its speed increases over the top surface, leading to a pressure drop above the wing compared to the pressure beneath it, creating lift.

The other principles listed do not pertain to this relationship between fluid speed and pressure. Pascal's Principle relates to the transmission of pressure in incompressible fluids, Archimedes' Principle addresses buoyancy, and Newton's Law of Viscosity describes the behavior of fluid flow in regards to viscosity but does not address the inverse relationship between speed and pressure.