# Homework Help: Another motion problem for constant acceleration

1. Sep 19, 2010

### chroncile

1. The problem statement, all variables and given/known data
A truck travels at a constant speed of 28.0 m/s in the fast lane of a two-lane highway. It approaches a stationary car stopped a the side of the road. When the truck is still 125 m behind the car, the car pulls out into the slow lane with an acceleration of 2.6 m/s2. How long will it take the truck to reach the car? (Answer is 6.32 s)

2. Relevant equations
N / A

3. The attempt at a solution
I have no idea how to do this :(

2. Sep 19, 2010

### Staff: Mentor

This is similar to the wolf/rabbit problem.

Write the position as a function of time for both the truck and the car. Measure from the initial position of the truck when the car starts moving. Set them equal.

3. Sep 19, 2010

### chroncile

I'm sorry, but could you please write that out in equation form? I am not a clever man.

4. Sep 19, 2010

### Staff: Mentor

Oh, you're clever enough.

You just solved an almost identical problem! Hint: The truck moves at constant speed; the car accelerates.