How to Use a Ping Pong Ball to Explain Bernoulli's Theorem

Bernoulli's theorem relates to pressure, velocity and the elevation of flow for an inviscid fluid. Bernoulli's theorem is helpful when racing car drivers are trying to reduce drag on their cars. Here's an experiment with a ping pong ball, which will leave your science class stupefied.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Ping pong ball
• Water bottle or soda bottle
• Scissors

1. Place the ping pong ball on the palm of your hand. Discuss how light the ball is to the touch. Blow on the ball so it moves around your palm easily. This will enhance the notion that the ball is ridiculously light.

2. Cut the water or soda bottle so just the top spout and a little of the top of the bottle remains. It will form a little cup.

3. Put the ping pong ball in the little cup that you've created.

4. Hold the cup flat as you place your head underneath and put your lips around the opening of the bottle.

5. Blow with all of your might and try and move the ping pong ball. You'll notice that you will not get very far and thus illustrate Bernoulli's Theorem that the pressure and flow of velocity, added to the gravity, give you a constant. Meaning the ping pong ball suspends just slightly off the edge of the homemade cup. Of course, if you add a few thousands pounds of pressure per square inch underneath the ping pong ball it will fly across the room. But no human will be able to pop the ping pong ball out of its container.