Question

8.Tarzan, mass 85kg, swings down from a tree limb. His feet touch the ground 4.0 m below the limb. How fast was Tarzan moving when he hit the ground?

Answer 1

As $mv^2/2=mgh$ hence $v=\sqrt{2gh}\approx\sqrt{2\sdot9.8\sdot4}\approx8.9m/s$