A rock falls from a cliff that is 320 m high. How long will it take the rock to reach the ground?

Answer 1

h(t) = (1/2)gt^2

1. h = height = 320 m
2. g = acceleration due to gravity = 9.8 m/s/s
3. t = time in seconds

320 = (1/2)(9.8)t^2

65.3 = t^2

Can you finish it? The units are seconds.