G-Force Measurement: Formulas for Launching into Orbit

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    G-force Measurement
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Discussion Overview

The discussion revolves around the measurement of g-forces experienced during the launch of a spacecraft into orbit. Participants explore various formulas and concepts related to g-force, including the acceleration experienced at different phases of the launch, such as ground level, during ascent, and in orbit.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Tim inquires about formulas for g-force measurement during launch, noting expected values of 1 G at ground, 3-5 G during launch, and 0 G in orbit.
  • One participant suggests that there is no general formula for g-force, indicating that it can vary significantly based on the launch profile, with possible values ranging from "500 G" for a short duration to a maximum of "2 G" during a slower ascent.
  • Another participant states that if the acceleration is approximately 20 m/s², astronauts would experience about 3 G, while also noting that g-force is nearly zero in orbit.
  • A different participant challenges the previous claim, arguing that if the acceleration is 20 m/s², the g-force experienced should be closer to 2 G, considering the need to counteract Earth's gravitational pull.
  • One participant asserts that the rocket is actually accelerating at about 30 m/s², not 20 m/s², which would affect the g-force experienced.
  • Tim later shares a link to Wikipedia for further information on g-force equations, suggesting external resources for calculations.

Areas of Agreement / Disagreement

Participants express differing views on the specific values of g-forces experienced during launch, with no consensus reached on the exact acceleration values or the corresponding g-forces. The discussion remains unresolved regarding the precise calculations and interpretations of g-force during launch.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about acceleration profiles and the definitions of g-force in different contexts. The varying interpretations of acceleration values contribute to the lack of consensus.

Sword7
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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
 
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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).
 
Sword7 said:
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.
 
pixel01 said:
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.
 
Pixel is correct. Relative to a free-falling reference frame, that rocket is accelerating upward at about 30 m/s^2, not 20.
 
D H said:
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!
 
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
 
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