This Will It Work is an easy experiment that explores the relationship between pressure differences using ping pong balls and straws.
Here’s what you need: 2 straws; modeling clay; ping pong balls; hair dryer.
Here’s how you do it: Put a piece of modeling clay on the table and stick a straw through it so that it sticks up. Do the same with the other straw and place them about 3 inches apart. Take a smaller piece of the modeling clay and put it on the ping pong ball and place the ball on top of the straw. Do the same with the other ping pong ball. Now take the hair dryer, turn it on and aim it directly between the two ping pong balls. You'll notice that the ping pong balls will get closer together.
Here's why it happened: This demonstrates how air always flows from high pressure to low pressure. The hair dryer is creating a fast-moving stream of air which results in low pressure. This is known as the Bernoulli Principle. The ping pong balls are being pushed in because the high pressure outside the balls flows toward the low pressure. Very cool.
Rating: It's a 4 and a half out of 5 beaker experiment. Easy to do, great demonstration and it actually does work!
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