Question

At the start of a race, a runner’s velocity changes from 0 to 4.0 m/s. It takes him 2 seconds to speed up. His acceleration is ______ m/s2.

Answer 1

To find the acceleration we divide the change of velocity by the change of time.
Change of velocity: 4 m/s
Change of time: 2 s

Acceleration = $\frac{4}{2} = 2$

So the answer: his acceleration is 2 m/s^2

Answer 2

His acceleration is, 2 m/s^2!

Hope this helps! :)