Ping Pong Pop

Pop that ball!

 

 

 

Category - Solids, Liquids & Gases

Key Idea - Air Pressure

 

Purpose - This demo shows the action of compressed air.

Figure A

 

Figure B

 

Figure C
Nature -  Demonstration
Materials -  A table tennis ball, both of your hands
Method - 
  1. Form your hands into the shape shown in Figure A.
  2. Gently wedge the table tennis ball as shown in Figure B. If this is done too tight it wont work, but it can't be too lose either.
  3. With your other slap air into the cup formed by your first hand, as shown in Figure C. It may take a bit of practice to get it going. As a guide, if you try doing it without the table tennis ball first, you should be able to feel the air coming through the hole where the ball should be. 
Safety - The ball does pop out at a fairly high speed so it is best not to point this at anyone.
Explanation - The second hand is scooping air into a confined space and compressing it. It tries to get out through the easiest exit, and if you've done it right, this exit involves pushing the table tennis ball aside.
Notes - The second hand is scooping air into a confined space and compressing it. It tries to get out through the easiest exit, and if you've done it right, this exit involves pushing the table tennis ball aside.

This Wizard was generously supplied by Mr. Alan Below.