1. The problem statement, all variables and given/known data As you are driving with a velocity of 75 km/h [N], you suddenly realize that there is a stalled vehicle in your lane 48.0m directly ahead. You react, applying the brakes to provide an acceleration of 4.80 m/s^2 . If you managed to avoid a collision what was your reaction time. 2. Relevant equations What was your reaction time? 3. The attempt at a solution First I wanted to find Vfinal so I used the kinematic equation Vf^2 = Vi^2 +2ad I used: Vi = 20.8333 m/s d = 48.0 m a = 4.80 m/s^2 This gave me Vf^2 = 29.9136 m/s Then to find the time I used Vf = Vi + at I got -1.89 s. The answer should be 0.13 s. What did I do wrong?