68. Blow Hard Scam
class: closer/challenge | impressiveness: 4/5 | factors: make ‘em look dumb, you smart | requires: bottle and bottle cap | watch full episode
This one’s a classic! They look like an idiot, and you prove that you’re smarter than they are. What’s not to love?
The Setup: Fold a bottle cap in half and place it inside the lip of a bottle set on its side, balanced right on the edge. Tell your friends that all they have to do to win a free drink is blow the bottle cap into the bottle.
Sounds simple, right? However, once they start, every puff of air only blows the bottle cap out of the bottle. It’s a really surprising effect, and most people immediately want to know why it won’t work.
The answer is in the air pressure. When they blow into the bottle, air pressure is increased on the inside, forcing the bottle cap out.
The Reversal: However you still can succeed where they fail: grab a small cocktail straw (the smaller, the better), and use short, sharp blasts of air, blown very close to the bottle cap. By using such a precisely-targeted blast of air, you’ll be able to carefully blow the bottle cap all the way inside the bottle.
Watch Demonstration (External link)