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michaelw
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Such as SkyLab? If the airplane got more horizontal velocity would things float?
michaelw said:Such as SkyLab? If the airplane got more horizontal velocity would things float?
At a certain specific value of horizontal velocity, yes !michaelw said:If there was no air resistance, does that mean that anything traveling at a horizontal velocity will continue at that velocity (orbit) forever?
This is only because there are some underlying assumptions in simple projectile motion (that rarely get mentioned )intuitively that's not true, because of simple projectile motion
That's almost exactly right !so what makes something orbit? is there a min or max speed horizontal speed necessary to get it to orbit? how can this speed be found? if the speed is lower than this magic speed, does that mean the object will fall to the earth, and if its higher then it will escape Earth's gravitational pull?
OlderDan said:...It also means the usual forces a body exerts to keep internal organs in place are now gone, and that funny feeling in your stomach appears...
I think you meant Apollo 13. Also, of course, it is not really zero gravity. It is a zero weight environment.jdavel said:By the way, for anyone who didn't already know, when Ron Howard was shooting his movie Apollo 11, he got to use a "vomit comet" to shoot all the zero gravity scenes. The realism makes other movies about space travel seem pretty lame!
Integral said:I once was a passenger in a small single engine plane that flew a parabolic trajectory for a few seconds. I do not think that it is particularly difficult to do. We need a pilots comment.
michaelw said:thanks everyone
one more problem :/
I seem to get different values for v if i use conservation of energy vs Newtons 1st law
Fg = Fc
mg = mv^2/R
v = sqrt(gR)
but..
W = Fd = Ek
mgR = mV^2/2
v = sqrt(2gR)
why are there 2 answers for v?
...because you are incorrectly using energy conservation.michaelw said:thanks everyone
one more problem :/
I seem to get different values for v if i use conservation of energy vs Newtons 1st law
Fg = Fc
mg = mv^2/R
v = sqrt(gR)
but..
W = Fd = Ek
mgR = mV^2/2
v = sqrt(2gR)
why are there 2 answers for v?
Objects appear to float in a satellite because they are in a state of freefall. This means that the satellite and its contents are falling towards the Earth at the same rate, giving the illusion of weightlessness. In an airplane, the force of gravity is counteracted by the upward force of lift, preventing objects from floating.
Weightlessness in a satellite is caused by the absence of a normal force. In other words, there is no surface or structure for objects to push against, so they appear to float. This is due to the fact that satellites are constantly in a state of freefall around the Earth.
No, objects cannot float in an airplane regardless of its altitude. As long as the airplane is in motion and experiencing lift, the force of gravity will still be present and prevent objects from floating. Weightlessness can only occur in a state of freefall.
In a satellite, the force of gravity is the dominant force, pulling objects towards the Earth. However, in an airplane, the force of gravity is countered by the upward force of lift, which allows the airplane to stay airborne. This results in a different gravitational experience for objects in each environment.
No, astronauts cannot float in an airplane like they do in space. In space, astronauts experience weightlessness because they are in a state of freefall around the Earth. In an airplane, the force of gravity is still present and counteracted by lift, preventing the same weightless experience.