A person drops a small rock from a bridge. If it takes 1.70 seconds for the rock to reach the water below the bridge, how high was the bridge above the water? please explain.

Answer 1

The distance it falls in t seconds after being dropped is
H = (1/2) g t^2

g is the acceleration of gravity, which you must have learned about by now. It is 9.8 m/s^2 on Earth.

Set t = 1.7 seconds and use the formault to solve for the height, H, in meters.