Subsonic Ping Pong Balls

On our Fresh Look on Physics, University of Utah physics demonstrator Ziggy Peacock fired a ping pong ball through a Coke can at just under the speed of sound.

How'd he do that? It's no magician's secret.

Peacock put a ping pong ball inside a length of PVC tubing. He covered each end with a piece of clear packing tape. He evacuated the air inside with a small vacuum pump. And then he punctured one taped end with a pocket knife.

The ball launches fast enough to pass through one and a half soda cans.

And leave one serious welt on a BYU physics professor. (Kids, don't try that at home.)