Floating Ping Pong Ball
You've seen Steve Spangler use blow dryers or industrial-sized blowers to levitate ping pong balls, beach balls, and send toilet paper flying through the air. You can replicate this levitating object phenomenon on a smaller scale using objects that are right in your home! The Floating Ping Pong Ball trick uses amazing principles of air that are sure to amaze anyone, from your science teacher to your parents to your neighbors!
- 1-liter bottle with cap
- Bendy straw
- Ping pong ball
- Large nail
- Scotch tape
- Box cutter or similar tool
- Near the top of a 1-liter bottle, approximately where the bottle stops curving and begins to straighten out, wrap a piece of tape. Try to wrap the tape as straight as possible.
- Using the tape as a guide, cut the top of the bottle off with the box cutters. Again, try to make your cut as straight as possible.
- *When performing this next step, make sure to find a work bench or similar surface.*
- Place the bottle cap, open side down, onto the work bench.
- Center a large nail on the top of the bottle cap and use a hammer to punch a hole in the cap.
- Pull the nail out of the bottle cap and you should have a nice, round hole.
- Test the bottle cap to see if a bendy straw will fit in the hole you've created. If it does, you're good to go. If the hole is too small, find a larger nail and widen the hole. If the hole is too large, you'll need to find another cap and use a smaller nail.
- Once you have the perfect bottle cap and hole, screw the cap onto the top of the bottle and place the short end of the bendy straw through the hole.
- You're ready to give the Floating Ping Pong Ball a try! Start blowing into the the straw (the end opposite the bottle) and place the ping pong ball over the stream of air.
- Much to the surprise of anyone watching (and probably you), the ping pong ball hovers in midair over the bottle. Wow!
Take It Further!
Are there any other objects that you can make float using the apparatus that you've created?
How Does It Work?
The Floating Ping Pong Ball is a wonderful example of Bernoulli's Principle, the same principle that allows heavier-than-air objects, like airplanes, to fly.
Bernoulli, an 18th century Swiss mathematician, discovered something quite unusual about moving air. He found that the faster air flows over the surface of something, the less the air pushes on that surface. That means that the air pressure on the object is lower than average.
The air from the straw, as you blow through it, produces the levitating ball phenomenon using Bernoulli's Principle. The fast air moving around the sides of the ball is at a lower pressure than the surrounding, stationary air. If you look closely, you'll see that the ball wobbles while it is levitating in midair. The ball is attempting to leave the area of low pressure, but the higher air pressure surrounding it forces it back into the low pressure area.