Pressure

JT, who is nine and full of questions, recently asked me how an airplane stays in the air. Hm...good question. As the homeschool teacher, I felt compelled to actually answer this question rather than pushing it off on my dear husband, the airplane fanatic. So I decided to do an entire unit on air. (Yawn) But it's what the kid is interested in learning, so off we go. I look up air pressure online (where else?) and discover Bernoulli's Principle. Yes, discovered as in never heard of it before, since I've never questioned WHY the airplanes stay in the air. I'm just happy that they do. This is what I learned:


"As the fluid passes over the central part of the tube more energy is used up as the molecules accelerate. This leaves less energy to exert pressure, and the pressure thus decreases. Concerning flight, Bernoulli's Principle has to do with the shape of an airplane's wing. The bottom is flat, while the top is curved. Air travels across the top and bottom in the same time, so air travels slower on the bottom (creating more pressure) and faster on top (creating less pressure). This keeps the plane in the air."



Huh? What? I had to read that approximately 3.5 trillion times to determine that I don't know what it means. And this was the simplest explanation I could find. Several failed experiments later, my head huuurrrtttss!! (she whines LOUDLY). I don't care how the $%#@ airplane stays in the air...just that it does. Is science class almost over? Oh well, I'm off to go prove that air can do work by making some tea and maybe we'll blow up a balloon or two to prove that it takes up space. I'm taking the kids to the museum that does a class on air pressure...so the pressure is off me. Ha! Ha! (Is that a twinge of hysteria in my voice?) Maybe I should open a bottle of wine instead of drinking tea. Think I could tweak that into a lesson on air pressure? Eh, probably not the best idea.