I know it has been a while since I have done g-force calcs but something does not look right with the calculations mkaibear presented. I thought acceleration was (final velocity - initial velocity) divided by time - not mulitplied by time.
A = ( V(final) - V(initial) ) / T(interval)
and this needs to be converted to g-force using 1grav = 9.8m/s/s
I found the message below and had some interesting comparisons.
Re: How do you calculate 'g-forces'?
Date: Tue Sep 8 12:21:33 1998
Posted By: Jason Goodman, Graduate Student, Massachusetts Institute of Technology
Area of science: Physics
ID: 904798508.Ph
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Message:
"g"-forces are really a measure of acceleration, which is the rate of change of velocity of an object. If a car accelerates from zero to sixty miles/hour in 6 seconds, it has an acceleration of 4.3 meters per second per second. That is, every second, its speed is 4.3 meters per second greater.
To convert this into "g-force", we compare this acceleration to the acceleration produced by gravity, which is 9.8 meters per second per second. The car is accelerating at about 0.4 times gravity, or 0.4 G's.
The "g" can be thought of as a unit of acceleration whose value is 9.8 m/s^2. In many cases (such as the one above), gravity has nothing to do with the situation. In others, it does. For example, the strength of gravity at the cloudtops of Jupiter is 2.5 G's, because objects would fall at 24.5 m/s^2 there.
So the "g" is simply a unit of measurement, but it's a convenient one for describing accelerations in terms people can identify with. Here's a handy table, reproduced from Physics, by O'hanian, 1989:
Protons in Fermilab accelerator 9e12 G
Ultracentrifuge 3e5 G (300,000 G)
Baseball struck by bat 3000 G
Soccer ball struck by foot 300 G
Automobile crash (100 km/h into wall) 100 G
Parachutist during opening of parachute 33 G
Gravity on surface of Sun 27 G
Explosive seat ejection from aircraft 15 G
F16 aircraft pulling out of dive 8 G
Loss of consciousness in man ("blackout") 7 G
Gravity on surface of Earth 1 G
Braking of automobile 0.8 G
Gravity on surface of Moon .17 G
Extra bonus factoid: if you lock your knees when you hit the ground after jumping off a 1-meter platform, the acceleration is about 50 G. So don't.
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