What does Bernoulli’s principle assert about fluid speed and pressure?

Bernoulli’s principle describes the relationship between the speed of a fluid and its pressure. Specifically, it asserts that as the speed of a fluid increases, the pressure within the fluid decreases. This principle is derived from the conservation of energy for flowing fluids, which indicates that the total mechanical energy in a streamline flow remains constant.

When a fluid flows through a constricted area, it must speed up to conserve mass, leading to a decrease in pressure in that region. This counterintuitive relationship is key in various applications, such as in the design of airplane wings, where the faster airflow over the wing creates lower pressure above it, generating lift.

In summary, the assertion that an increase in fluid speed occurs simultaneously with a decrease in pressure aligns perfectly with Bernoulli's principle, illustrating how the properties of fluid dynamics interact in real-world scenarios.