Investigating Torricelli’s Law (and More) with a 19th-Century Bottle

The phenomenon of emerging water jets from the holes of containers has been extensively studied; nevertheless, it continues to inspire researchers and teachers. The main aspects of the recent studies concern: the range of the jets trajectories; the extension of Bernoulli’s equation, of which Torricelli’s expression represents an ideal situation, to real fluids; and the measure of the jets’ speed and the drainage time in dependence on the fluid system geometry and wetting conditions. The focus of this paper is to discuss Torricelli’s relation between jet speed and hole depth in the case of a 19th-century glass bottle featuring three lateral holes. Measurements of the free water level displacements and jet speed from the holes have been carried out with 11th-grade students.