A truck on a straight road starts from rest and accelerates at 3.0 m/s2 until it reaches a speed of 18.1 m/s. Then the truck travels for 24.5 s at constant speed until the brakes are applied, stopping the truck in a uniform manner in an additional 5.7 s. (a) How long is the truck in motion?

Answer 1

V = Vo +a*t = 18.1 m/s.
0 + 3*t = 18.1
t1 = 6.03 s.

t2 = 24.5 s.

t3 = 5.7 s.

T = t1 + t2 + t3
T = 6.03 + 24.5 + 5.7 = 36.23 s.