Question

A ball is kicked horizontally, at 16.8 m/s, from the edge of a bridge over a smooth flowing river. It lands on the water at a distance 30.7 m from the edge of the bridge. How high is the bridge?

Assume a gravitational acceleration of 9.8 m/s^2 and that there is no air resistance.

Answer 1

The height of bridge is 14.4 m

Step-by-step explanation:

According to third equation of motion

2aS = Vf² - Vi²

Here a = g = 9.8 m.s²

Vf = 0

Vi = 16.8 m/s

So putting the values

2aS = Vf² - Vi²

2 (9.8) (S) = 0 - (16.8)²

19.6 S = 282.24

S = 282.24 / 19.6

S = 14.4 m