1. The problem statement, all variables and given/known data A 47,000 kg locomotive is traveling at 13 m/s when its engine and brakes both fail. How far will the locomotive roll before it comes to a stop? 2. Relevant equations v_f^2 = v_i^2 + 2ad F=ma 3. The attempt at a solution I've tried making a force diagram and working from there, but I'm not even sure if that's right. If I had to guess, I would solve for acceleration and use the equation above to get the desired distance, but I don't know how to do that! Please help!