What is Bernoulli's principle in relation to fluid dynamics?

Bernoulli's principle states that in a streamline flow of an incompressible fluid, an increase in the fluid's velocity occurs simultaneously with a decrease in pressure within the fluid. This phenomenon occurs due to the conservation of energy in fluid dynamics, where the total mechanical energy of the flowing fluid remains constant. As the fluid speeds up, the kinetic energy increases, which leads to a reduction in the potential energy manifested as pressure.

Thus, when the fluid moves faster, its pressure drops. This characteristic aligns precisely with the assertion that an increase in velocity decreases pressure. It illustrates how the fundamental balance between kinetic energy and pressure energy operates in flowing fluids, which is essential for understanding various applications in engineering, such as in aerodynamics and the design of fluid systems.