How high is yours?

I said I would put this in. Just a quick spreadsheet graph so you know how high a cliff is when you throw something off it and count how long it takes to get to the bottom. The formula used is: s = ut + 0.5at^2, where s height, u = initial velocity, a = acceleration = gravity = 9.8m/s^2, t = time.

NB This formula doesn't take account of friction which means that for all our purposes, the height maybe negligibly less than the graph shows.