Torricelli's Law states that the speed of fluid flowing out of an opening under the influence of gravity is proportional to the square root of the height of the fluid above the opening. This principle can be observed in various scenarios, such as water draining from a tank. The law is derived from Bernoulli's Principle, which relates the speed of a fluid to its pressure and height. According to Torricelli's Law, the formula for the exit speed v of the fluid is given by v = \sqrt2gh , where g is the acceleration due to gravity and h is the height of the fluid column. This relationship helps in understanding fluid dynamics and is applicable in engineering and physics.