Physics

Problem

A ball is released from rest from the top of a tower. Taking

g = 9.8\,\text{m/s}^2

, what is its speed after

4\,\text{s}

? a)

78.4\,\text{m/s}

40.0\,\text{m/s}

39.2\,\text{m/s}

19.6\,\text{m/s}