Question

a 15 kilogram ball is rolling at 20 meters per second. the kinetic energy is how many joules?

Answer 1

To find the kinetic energy, we have to use the following formula

$K=\frac{1}{2}\cdot m\cdot v^2$

Where m = 15 kg and v = 20 m/s.

$\begin{gathered} K=\frac{1}{2}\cdot15\operatorname{kg}\cdot(20m/s)^2 \\ K=\frac{1}{2}\cdot15\operatorname{kg}\cdot400m^2/s^2 \\ K=3,000J \end{gathered}$

Therefore, the kinetic energy is 3,000 Joules.