Browse Teasers
Search Teasers

## The Straw that Broke the Champion's Lungs

Science brain teasers require understanding of the physical or biological world and the laws that govern it.

 Puzzle ID: #38119 Fun: (3.06) Difficulty: (1.96) Category: Science Submitted By: Hrsemn4

A physics teacher used to enjoy tricking his students into learning science facts. One day, he placed an 8-ounce glass filled with water on a table. He then produced 2 straws; one straw he placed into the glass of water and the other he held outside the glass.

"Class," he said, "I am willing to fund a pizza party for the class if any one of you can drink this glass of water in 5 minutes using only these two straws." The class was amazed; this would be an easy task for any of them. "There are a few conditions," he continued. "You must drink using both straws at the same time. You must drink using slow and steady draws. You cannot block or obstruct either straw in any way. You cannot lift or tilt the glass off of the table. And finally, one straw must remain outside of the glass."

The class selected their champion and felt confident that they would be enjoying pizza at the same time next week. Five minutes later, the champion returned to his seat, defeated, and the class sat with jaws agape. Being a good sport, the teacher still bought pizza for the class the next week, confident they would never forget the lesson he taught them.

Why did the champion fail?

The teacher knew a lot about air pressure. He knew that air from a high-pressure area would always seek to fill an area of lower pressure, such as a vacuum. He also knew that a straw worked on this principle. Drawing on the straw creates a low-pressure area in the mouth; air pressure pushes down on the water and forces it up into the straw. When he placed the second straw outside the glass, and thus outside the water, he gave the air a more direct path from the high-pressure area to the low-pressure area. With slow steady draws on the straws, the air will easily rush in through the second straw to fill the low-pressure area, and the water will remain in the glass. Try it at home!
Hide

## What Next?

See another brain teaser just like this one...

Or, just get a random brain teaser

If you become a registered user you can vote on this brain teaser, keep track of
which ones you have seen, and even make your own.

 eraserheads0909 Sep 05, 2007 I had already tried it GebbieRose Sep 05, 2007 Glad people are still submitting science teasers. Good job! anubistheta Sep 08, 2007 I miss fluid mechanics like this. Good teaser! IQ_master Sep 18, 2007 That was fun!! i wanna try it at home!!! Emmanovi Sep 26, 2007 Not sure if this is breaking the rules... but could one straw be placed in the other one at the end (like joining them together to make a longer one) and then this used? One of the straws could remain outside the glass, and you are still using both... Or am I missing something? Anyway, great teaser I like these science ones, they make you think rationally about the physics and dynamics of the problem CatsAreCute Jan 15, 2008 Nice one! Kind of easy. Starriddler Mar 14, 2008 Good one. tonjawithaj Apr 14, 2008 I agree with Em! Wa11E Sep 24, 2008 Yes the champ should have tried joining them - but to do it in a way that is reaonably sir tight would be the hard part tova_l Jun 24, 2009 WOW! Great teaser! I love science! I didn't know that thing about air pressure, it's very interesting!!! Thanks for teaching me something new! princess2007 Mar 09, 2011 Easy.