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Please Pass the Science - Potatoes for Fun and Profit
by Scott Berk

Most will agree that the potato is a versatile food which appears ubiquitously in a wide variety of dishes. Indeed, the use of this tasty tuber even crosses cultural boundaries, from the thoroughly American meat and potatoes to the more exotic curries of East Asia. However, this is not a discussion of the inner workings of potato plants, their composition, nor even their colorful history. Rather, I am here to tell you how to use one to procure large sums of money.

Now before I start, I feel I must say a few words about betting in general. As a man of science, I have a keen instinct of probability and chance. I rarely make a bet I cannot win, and, at the very least, I never bet unless the odds are in my favor. Perhaps it's the determinist in me - not willing to make predictions unless the physical laws governing that prediction are well elaborated and explicitly solvable. But quantum mechanics shows us that even what we think is completely predictable is not, at a small enough level. God DOES play dice with the universe. God does NOT, however, play Lotto. Ah, the lottery. I simply cannot understand why people throw their money away on it. Sure, you may win big, but your chances of getting struck by lightning are better. Hell, your chances of getting struck by lightning on your BIRTHDAY are better! In fact, I tend to agree with the person who once said, "Lotteries are a tax on the stupid." But I digress ...

Here is a bet where the odds are stacked heavily in your favor, especially if your victim does not have a keen appreciation of science. All you need is a common plastic drinking straw and an uncooked potato. Challenge your victim to push the straw through the potato. Now, the person may simply reject the idea outright, or perhaps make a token effort, but the straw just isn't strong enough. Or is it? After they have either given up or called you crazy, demonstrate your potato prowess. Hold the straw such that your finger covers one end, and jam the other end into the potato. If you keep the end closed and move fast enough, the straw goes right through. You are left with a true spectacle, rivaled only by shafts of wheat driven through telephone poles by tornados. And, strangely enough, a similar property is at work in both instances - namely, AIR PRESSURE.

A drinking straw is not very rigid on its own. It bends easily with a minimum of force. However, if you hold one end of the straw closed and jam the other end into a potato (or anything else of similar hardness), air is trapped within the straw. Now, gases can contract quite a bit, but in doing so, they build up pressure. The pressure of the air inside the straw is enough to keep it rigid as it tunnels through the tuber. If the air is allowed to escape, no pressure is built up, and the straw bends or breaks.

I use this property quite often - not to poke straws through potatoes, but rather to insert them into those horrid plastic soft drink lids which are dispensed at various fast food restaurants and convenience stores. I find that the "Cover and Jam" method penetrates the pre-cut plastic top quickly and effectively. Try it once and you'll be a convert for life. So, the next time you need a quick buck (or a Big Gulp (tm)), don't forget the potato and the straw, and be sure to send a portion of the profits to me. After all, you couldn't have done it without air pressure, and ... SCIENCE!

A recent "Beakman's World" television show presented an alternative explanation to the "straw and potato" experiment, invoking the "structural integrity of a cylinder" as the SOLE explanation for this dramatic effect. Covering the straw, Beakman maintains, makes no difference. Well, I've run a series of control experiments and SCIENTIFICALLY determined that covering the straw is essential to success. It's the air pressure. Fuck you, Beakman.

What is the greenhouse effect? How does a rainbow happen? Is it true that the stuff inside a Lava Lamp could be the key to a cheap and clean fuel source? Send your science questions to Dr. Scott Berk.

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