A car sits in an entrance ramp to a freeway, waiting for a break in the traffic. The driver sees a small gap between a van and an 18-wheel truck and accelerates with constant acceleration along the ramp and onto the freeway. The car starts from rest, moves in a straight line, and has a speed of 15.0m/s when it reaches the end of the ramp, which has length 125m .

Question

(a) What is the acceleration of the car?

(b) How much time does it take the car to travel the length of the ramp?

Answer 1

a. V^2 = Vo^2 + 2a*d
a=(V^2-Vo^2)/2d = (15^2-0)/250=0.9 m/s^2

b. V = Vo + a*t
t = (V-Vo)/a = (15-0)/0.9 = 16.67 s.

Answer 2

1515