Kinetics in Physics

Question

An Olympic diver is on a diving platform 7.70 m above the water. To start her dive, she runs off of the platform with a speed of 1.19 m/s in the horizontal direction. What is the diver's speed, in m/s, just before she enters the water?

Answer 1

Hi.

We're going to assume that there is no air resistance, which means that the horizontal velocity of the diver remains constant.

Here is the equation we'll use:

v² (y, final) = v² (initial) + 2ax

where v² (y, final) is the diver's ending vertical velocity (i.e., right before impact with the water), v² (initial) is the diver's velocity as she leaves the diving board, a is acceleration of gravity, and x is vertical displacement.

v (y, final) = √v² (initial) + √2ax = √(7.70 m/s)² + √2(9.81 m/s/s) (7.70 m) = √59.29 + √302.148 = 7.70 + 17.3824 = 25.1 m/s