So 19.5 meters in 2 seconds = 9.75 meters/ second so yes that should be 1 G,however that would be the "average G's for the run not the maximum.You should start off with a high initial G and then taper off as your speed increases and the acceleration decreases but this is starting to get into differenciation and I can neither spell it correctly or confidently come up with the correct formula to plot the curve.
