Question

A ball is thrown horizontally from the top of a building which is 30.6 meters tall. It lands 50.0 meters from the base of the building.

What was the launch speed of the ball?

Answer 1

First, we need the time before the ball hits the ground. This would be:
0=30.6-4.9t²
4.9t²=30.6
t=2.5 secs
50 meters/2.5 secs=20 m/s as the speed of the ball
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