I just want to know if the gravity in after effects is m / s^2 or if it's a ratio (ex: ratio of 1 would be 1 time the earth gravity). I want to know that because if I want to reproduce something falling in after effects I could put 9.8 m / s^2 like the real gravity of earth.
Sorry for my english, I know I'm not using the exact words...
Agreed. As all the plugins I can think of come from different creators and at different times (CC Particle World, Shatter, Particular etc) I doubt there is any correlation between their various schemes of applying gravity.
More to the point, aside from the interest factor, is it really important? Surely the result should be gauged visually rather than scientifically. Adjust the parameter until you achieve the desired result, simple as that.