A Stroll with a Ball

Let's take a look!

Watch the video on YouTube.

What kind of experiment is this?

Experimental procedure and explanation:

• Let us utilize the Coanda effect to manipulate a ball.
• Use a dryer to focus a direct flow on top of a ball. When you move the dryer, the ball moves with it.
• Because of the round shape, the flow follows the ball surface, and so the ball and the flow draw each other together.
• You can use water and observe the same effect.

(The flow passes around the ball and reaches the floor. The flow could either diverge along the floor or converge in the direction that was bent due to the Coanda effect. However, the flow that reached the floor does not have a significant effect on the behavior of the ball.)

[Keywords]	Coanda effect, momentum theory
[Related items]	A Single Plastic Bottle
[Reference]	“Illustrated Fluid Dynamics Trivia,” by Ryozo Ishiwata, Natsume Publishing, pp. 214-215 and 206-209 “The Wonders of Flow,” Japan Society of Mechanical Engineering, Koudansha Blue Backs, pp.140-143