I know.
How can a 400 ton plane stay in the air when physics say everything that goes up must come down. When people fall off a building why does'nt the air support them to fly?
2007-12-05 06:47:19 · 5 answers · asked by grfisgd 6 in Science & Mathematics ➔ Physics
Aerodynamics. The plane would fall if the lift generated by the wings was insufficient to keep its mass airborne. (Eventually the plane will come down, once it runs out of fuel necessary to generate the forward velocity required to generate lift from the wings).
2007-12-05 06:51:12 · answer #1 · answered by Anonymous · 2⤊ 0⤋
If gravity were then only force at work when a plane is in the air then if it goes up, it will come down. But, when the plane is in the air there is another force at work. The other force at work pushes upward on the wing, read about bernoulli principle to see how that works. One the force on the wings is gone the plane will go back down.
Failling off a building, your speed will increase while fallin, but there is a point where your speed will no longer increase becasue of the air resistnace. The force on your body provided by the flowing air will increase until it cancels out your weight . Once that happens you will not be able to increase in speed any more, so you will remain at the speed that you were going. The air is the thing that slows you down, so in order to stay afloat you would have to continuously gain more and more speed so that the air provides enough Force (due to air resistnace) to keep you up. But, as I said earlier there is a limit to how fast you can fall, and the speed at which the air whips by you as you fall is not enough to hold you up.
2007-12-05 15:22:04 · answer #2 · answered by Brian 6 · 1⤊ 0⤋
Physics doesn't really say that everything that goes up must come down. We've launched things into space that have never come back and never will.
Planes stay up by making clever use of the force the air exerts upward on their wings as they fly.
People don't come with wings -- but if they have a hang glider on hand they certainly can get the air to support them to fly as they hang from it..
2007-12-05 15:10:59 · answer #3 · answered by Steve H 5 · 0⤊ 0⤋
Well if a person had a jet pack then wouldn't they fly? Planes have engines to push the air.
2007-12-05 14:51:09 · answer #4 · answered by stoneylobster 3 · 1⤊ 0⤋
it has to do with air pressure. the wings are shaped so that there is more pressure pushing up than gravity pushing down.
planes do come down eventually though.
humans don't have wings, so we can't change how the air acts on our bodies, so we can't create the lift necessary.
2007-12-05 15:27:28 · answer #5 · answered by Anonymous · 0⤊ 0⤋