Question

A race car is traveling at +76 m/s when is slows down at -9m/s2 for 4 seconds. What is his new velocity?

Answer 1

apply v = u + at
where u = 76 m/s , t = 4 s, a = -9m/s
v = 76 + (-9×4)
v = 76 - 36
v = 40 m /s

Answer 2

Answer: 40m/s

Explanation:

vi = 76 m/s

a = -9m/s^2

t = 4 s

vf = ?

vf = vi + at

vf = 76 + (-9) x 4

-36 + 76 = 40

Final answer = 40m/s