Challenge a friend to a game of Bernoulli Ball! It looks easy, but you will quickly see that there are subtle forces at work which require shrewd analysis and manipulation for accurate shooting. You will need a hair dryer with a cylindrical nozzle, ping pong balls, and two or three cardboard boxes of different sizes.
a. First build the game. Place the smaller cardboard box inside a larger box to serve as the target. Place the boxes in front of a wall (you won’t have to chase as many stray balls that way).b. To play the game, the player sits in a chair or on a stool with the hair dryer about 1 meter away from the target box. Set the hair dryer on the cold-air setting (or the lowest setting possible). Turn the dryer on and point the nozzle straight up. Place a ping pong ball in the airstream of the hair dryer, about 1" above the nozzle. The player then “shoots” the ball by smoothly tilting the dryer downward so that the ball falls out of the airstream and continues on a curved path toward the target.c. Here are the rules for the game. Each player is allowed five practice shots and five shots for official score. If the ball hits the dryer, the player gets to try again. Scores: inner box = 3 points, outer box = 1 point, outside either box = 0 points.d. When you are done, answer the following questions:
1. Why does the ball stay in the airstream when the dryer is pointing straight up?2. Does the ball fall out of the airstream as soon as you start to tilt the gun?3. Why or why not? Why does the ball leave the airstream when you continue to tilt the hair dryer?4. After playing the game, do you have any suggestions for someone who has never played it?
