The Venturi throat is a narrow section of a tube or pipe that is part of a Venturi meter, which measures fluid flow. As fluid passes through this constricted area, its velocity increases while the pressure decreases, demonstrating the principle of conservation of energy. This effect is used in various applications, including measuring flow rates in water systems and in carburetors for internal combustion engines. In a Venturi effect, the change in pressure and velocity can be utilized to create suction, allowing for mixing of fluids or gases. This principle is essential in devices like spray nozzles and atomizers, where it helps to draw in additional substances, enhancing performance and efficiency.