Question

a 40 kg runner is running at a speed of 3 m/s. how much kinetic energy does the runner have? remember : $e_k = \frac{1}{2}mv^2$ $e_k = ?$ j

Explanation:

Step1: Identify given values

Mass $m = 40\ \text{kg}$, speed $v = 3\ \text{m/s}$

Step2: Substitute into kinetic energy formula

$$E_K = \frac{1}{2}mv^2 = \frac{1}{2} \times 40 \times 3^2$$

Step3: Calculate step-by-step

First compute $3^2 = 9$, then $\frac{1}{2} \times 40 = 20$, finally $20 \times 9 = 180$

Answer:

$180$