Home > Activity > Enjoy Fluid Experiments Lab. > Slither


Let's take a look!

What type of experiment is this?

Experimental procedure and explanation:

  • Let’s remove the caterpillar-like object from the tube with the wind from a hair dryer. The object is a polystyrene foam ball with a diameter of 6 cm and five balls with diameters of 4 cm connected by a thin string. The tube diameter (inner diameter) is 6.3 cm.
  • When aiming at the center of the ball and blowing the wind, the caterpillar-like object can be removed. The principle is the same as "Remove a ball or egg from the tube". There is a large pressure where the air flow turns back, and the pressure below this is about the same. Therefore, the pressure on the underside of the ball pushes up more than the force pushing up from above, and the object floats up. When the first ball comes out, subsequently letting the air flow into the tube will result in the remaining balls coming out (there are times when they come out from the momentum of the first ball).
  • In this experiment, the center of the ball was the target, but there is also a method of letting air flow along the wall of the tube (Removing a Ball from a Cylinder).
[Keywords] Momentum theory, pressure
[Related items] Remove a ball or egg from the tube, Float an egg, Removing a Ball from a Cylinder

“Illustrated Fluid Dynamics Trivia,” by Ryozo Ishiwata, Natsume Publishing, P200-201

◀ Back Next ▶

Last Update:3.3.2017