152k views
21 votes
Joaquin is at rest at the top of a hill on a skateboard. Four seconds later, he reaches the bottom of the hill at a final velocity of 20 m/s. What was his acceleration?

1 Answer

6 votes

Step-by-step explanation:

Given: Initial Velocity=0

Final Velocity= 20 m/s

Time= 4 s

Accleration: Unknowns

Use kinematic equation


v _(f) = v _(i) + at


20 = 0 + at


(20m)/(s) = a(4s)


a = \frac{5m}{ {s}^(2) }

so a = 5 m/s^2

User Bwroga
by
7.1k points