According to Bernoulli's Principle, what happens to the pressure of a fluid as its velocity increases?

• A. Pressure increases
• B. Pressure remains constant
• C. Pressure decreases
• D. Pressure fluctuates

Answer: (C)

Bernoulli’s Principle states that in a fluid flow, an increase in the fluid's velocity leads to a decrease in pressure. This phenomenon occurs because the total energy in a flowing fluid must remain constant when the flow is steady and incompressible, and is influenced by the conservation of energy principle. As the velocity of a fluid increases, the kinetic energy of the fluid also increases, which must be balanced by a corresponding decrease in the fluid's potential energy, typically observed as pressure.

In more practical terms, when fluid travels through a constricted area or along a surface that causes it to speed up, such as in a venturi tube or an airfoil, the pressure exerted by the fluid on its surroundings decreases. This principle is fundamental in various applications, including aviation, where the shape of an airplane wing causes air to move faster above the wing than below, thus generating lift due to lowered pressure above the wing.

Understanding this principle is crucial for fields such as fluid dynamics, engineering, and various scientific disciplines, highlighting the relationship between fluid velocity and pressure in motion.