When sprinting, Rich can accelerate at 0.5 m/s^2. How many seconds would it take Rich to sprint a distance of 200 m if he starts from rest?

Dec 9, 2015

$28.28 \text{s}$

Explanation:

Use:

$s = u t + \frac{1}{2} a {t}^{2}$

Since $u = 0$ then

$s = \frac{1}{2} a {t}^{2}$

$\therefore t = \sqrt{\frac{2 s}{a}} = \sqrt{\frac{2 \times 200}{0.5}} = 28.28 \text{s}$

This assumes that he maintains the same acceleration throughout the race.