# Rocket launch that produces a certain g-force

1. Jan 1, 2009

### jolande

How do you calculate the period during rocket launch that produces a certain g-force? Is there a formula to work this out?

Last edited by a moderator: Mar 7, 2013
2. Jan 1, 2009

### Gnosis

Re: G-Force

My apologies HallsofIvy. I've been experiencing ISP issues and getting bumped repeatedly, so I typed up what I thought may have been the "quick and easy" explanation, posted it, and didn't have a chance to thoroughly recheck it before I got bumped again. It took me the last 20 minutes or so just to get reconnected.

Last edited: Jan 1, 2009
3. Jan 1, 2009

### montoyas7940

Re: G-Force

It will depend on each specific situation. One g of acceleration is about 9.8 meters per second per second. 9.8$$m/s^2$$

So at the point in the launch the rockets speed is changing by 9.8$$m/s^2$$ the craft is experiencing one g over and above the acceleration due to gravity.

4. Jan 1, 2009

### HallsofIvy

Staff Emeritus
Re: G-Force

??? G force has nothing to do with velocity- it depends on acceleration. Was that just a repeated misprint? (Referring to Gnosis' post.) The formula should be (a/g)+ 1, not (v/g)+ 1. That is, you feel your normal weight due to gravity plus an additional "weight" due to the force causing the acceleration.