Floating Balls

Fri, Feb 3, 2012

Materials: Wet/dry vacuum (use the blow setting), balls (tennis, racquetball, ping pong, styrofoam, beach ball...), plastic bottle (2L or smaller)

Activity: Make a funnel out of the plastic bottle. Drop the funnel into the vacuum hose. (Mine fit! If your's doesn't, you can make a funnel out of paperboard and tape it to the vacuum hose or hair dryer.) Face the funnel toward the sky. Drop a ball in the funnel. Set the vacuum on “blow” setting and turn it on. What happens? Some balls spin inside of the funnel. Face the funnel towards the ground. Some balls continue to spin inside of the funnel!

Research Questions: Does the size or weight of the ball matter? What happens without a funnel, or a different size funnel?

Resources:

Floating Balls and Flying Toilet Paper

Tags: Air Pressure Gas Force and Motion 2012