Question

A 72.0-kg skydiver is falling at a terminal velocity of 79.0 m/s. Which equation should be used to calculate the diver’s kinetic energy?

Answer 1

The correct equation to use to calculate the kinetic energy of an object is:

$K=\frac{1}{2}mv^2$

where

m is the mass of the object

v is its speed

In this problem, the mass of the skydiver is $m=72.0 kg$, while its speed is $v=79.0 m/s$, therefore his kinetic energy is

$K=\frac{1}{2}(72.0 kg)(79.0 m/s)^2=2.25 \cdot 10^5 J$

Answer 2

The Kinetic energy formula will be used:

Ek= 1/2mv^2

Ek= 1/2x72x79^2

Ek= 224,676 Joules