A simple and inexpensive way to demonstrate submarine theory and Archimedes' principle

Drawing the air out of the ball with the syringe creates a vacuum. Water enters the ball through the nut in the bottom of the ball causing the ball to sink. The reading on the syringe provides the volume of air that was replaced by water within
the ball allowing the student to quantitatively test Archimedes principle. Then, by slowly filling the ball with air the water is forced out and the ball will rise. For a lesson idea
Ball Diameter: 3 inches / 75mm
Syringe Capacity: 60ml
Latex hose length:  20 inches / 500mm