Question

A runner was going at a velocity of 12 m/s but got tired and, after 4 seconds, slowed down to 8 m/s. What is the runners acceleration?

Answer 1

-4.0 m/s²

Step-by-step explanation:

a = Δv/Δt = (8 m/s - 12 m/2) / 4 s = -4.0 m/s²

the negative sign means the runner was slowing down (decelerating)