# Torricelli's Law

Written by Jerry Ratzlaff on . Posted in Fluid Dynamics

Torricelli's law, also called Torricelli's principle or Torricelli's theorem, is the fluid efflux velocity flowing through an orifice under gravity at the bottom of a tank filled to a depth.  This is the same velocity from the orifice as a falling body over the same height due to gravity.

## Torricelli's law formula

$$\large{ v = \sqrt{ 2 \; g \; h } }$$
Symbol English Metric
$$\large{ v }$$ = velocity $$\large{\frac{ft}{sec}}$$ $$\large{\frac{m}{s}}$$
$$\large{ h }$$  (Greek symbol rho) = height $$\large{ft}$$ $$\large{m}$$
$$\large{ g }$$ = gravitational acceleration $$\large{\frac{ft}{sec^2}}$$ $$\large{\frac{m}{s^2}}$$