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Sword7
Mar21-09, 09:52 PM
Hello folks,

Does anyone know any formula about g-force measurement when launching into orbit? For example, 1 G at ground, 3-5 G during launching, 0 G at orbit.

Thanks,
Tim

fluidistic
Mar21-09, 10:04 PM
Hi,
I don't think there's a general formula. For example it could be say "500 G" for a little time (launching time) and then you could put the satellite into orbit.
It could also be accelerated very slowly, so G wouldn't get higher than "2 G" during its trip from Earth's ground to Earth's orbit.
But in any case you need to accelerate the satellite more than g (that is, around 9.8m/s^2).

pixel01
Mar21-09, 11:45 PM
Hello folks,

Does anyone know any formula about g-force measurement when launching into orbit? For example, 1 G at ground, 3-5 G during launching, 0 G at orbit.

Thanks,
Tim

One G equals to 9.8m/s2. You have 1 G at the surface of the Earth as well. So before launching, the g-force is 1 G (just like you and me have). At the launch, if the acceleration is ~20m/s2 so the astronauts bear about 3 G , and so on. In orbit, the g-force is almost zero and you have O G.

fluidistic
Mar22-09, 10:53 AM
One G equals to 9.8m/s2. You have 1 G at the surface of the Earth as well. So before launching, the g-force is 1 G (just like you and me have). At the launch, if the acceleration is ~20m/s2 so the astronauts bear about 3 G , and so on. In orbit, the g-force is almost zero and you have O G.

Are you sure pixel, that if the acceleration is about 20m/s^2 then the astronauts bears 3 G?
I wouldn't say so. For me it's about 2 G. Even if the force required to do so has to "cancel out" the "1 G" acceleration we feel on Earth's ground and then has to propulse the astronauts to an acceleration of 20 m/s^2.

D H
Mar22-09, 11:39 AM
Pixel is correct. Relative to a free-falling reference frame, that rocket is accelerating upward at about 30 m/s^2, not 20.

fluidistic
Mar22-09, 01:41 PM
Pixel is correct. Relative to a free-falling reference frame, that rocket is accelerating upward at about 30 m/s^2, not 20.

Ok then I'm wrong.
I get it now!

Sword7
Mar22-09, 10:33 PM
Hello folks,

I found equation for g-force when I searched through google. Look at http://en.wikipedia.org/wiki/G-force about equation of g-force for calculation.

Tim