Bernoulli's principle states that for the streamline flow of an ideal (incompressible and non-viscous) fluid, the sum of pressure energy, kinetic energy, and potential energy per unit volume remains constant at every point along a streamline.

Mathematical Expression: $P + \frac{1}{2}\rho v^2 + \rho gh = \text{constant}$

Where: $P$ is the static pressure. $\frac{1}{2}\rho v^2$ is the kinetic energy per unit volume.

• $\rho gh$ is the potential energy per unit volume.