Kinetic Energy Physics Example 3

Follow the full solution, then compare it with the other examples linked below.

medium

0.5 \text{ kg}

ball has

100 \text{ J}

of kinetic energy. What is its speed?

1
Rearrange $KE = \frac{1}{2}mv^2$ for $v$ .
2
$v = \sqrt{\frac{2 \times KE}{m}} = \sqrt{\frac{200}{0.5}} = \sqrt{400} = 20 \text{ m/s}$

Answer

v = 20 \text{ m/s}

The kinetic energy formula can be rearranged to find any unknown. Knowing the KE and mass allows us to determine the speed.

About Kinetic Energy

The energy an object possesses by virtue of its motion, equal to one-half times its mass times the square of its velocity.

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