physics
posted by Anonymous .
A person standing at the edge of a seaside cliff kicks a stone over the edge with a speed of vi = 16 m/s. The cliff is h = 60 m above the water's surface, as shown below. How long does it take for the stone to fall to the water? With what speed does it strike the water?

h = Vo*t + 0.5g*t^2 = 60 m.
16t + 4.9t^2 = 60
4.9t^2 + 16t  60 = 0
Use Quad. Formula.
Tf = 2.23 s. = Fall time.
V = Vo + gt = 16 + 9.8*2.23 = 37.86 m/s.