Going fast down the water slide
I have been thinking lately on how to go down a water slide the fastest (.The big kind that they have at the local YMCA s. ) If you ask them, the lifeguard will almost always tell you the same thing: “Put your hands above your head and get into tight streamline while crossing your legs and laying flat on your back.” Putting your hands above your head will expose your shoulder blades more, so that you are actually using them as a kind of skid. Crossing your legs lets you use your heel as one too. So, really, what they tell you makes pretty good sense: only three parts of your body are touching the slide at once, and your entire body weight is divided onto just three points ( I think? ). With this technique I can get down a 25 foot slide in about 10~12 seconds.
If you think about it, however, the water on the slide is only going one direction, so the more water that hits you, the more pressure there is against you. If you sit up straight, more water is hitting you and so you should go faster, right? Wrong. You are not streamlined, so even if the water is going the same direction you are, you won’t be able to cut through it as fast, and you want to go fastER than the water is going. Also, your body weight is divided over a larger surface. ( An upside-down cone of metal will go down the slide faster than a block of metal of the same weight. I think. )
All of this is just speculation, and I have almost absolutely no knowledge in the field, so don’t bet yer life on it cuz it might be totally bogus. :mrgreen: