1. The problem statement, all variables and given/known data A car is travelling on cruise control at velocity v1. Ahead on the road, a distance x away, a truck is travelling at a slower constant velocity v2. What is the maximum constant acceleration the car needs to avoid hitting the truck? 2. Relevant equations 3. The attempt at a solution The only thing I could think of solving was the time when they would collide. So I wrote like this: v2*t + x = v1*t x = t(v1 - v2) t= x/(v1-v2) I'm not sure if this is the right way to start the problem and if it is I don't know where I can go with this.