posted by gemmma .
A hot-air balloon is ascending at the rate of 11 m/s and is 51 m above the ground when a package is dropped over the side. (a) How long does the package take to reach the ground? (b) With what speed does it hit the ground?
Consider the package:
hf=hi+vi*t-1/2 g t^2
vi^2=2*11*51 so put that vi in the above equation. Hf=0, hi=51, solve for t.