# Car rolling and Friction

## Homework Statement

a. A 49,000 kg locomotive is traveling at 11 m/s when its engine and brakes both fail. How far will the locomotive roll before it comes to a stop?
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b. Determine the stopping distance if the locomotive had the same initial velocity but was "low on diesel" so its mass was only 35,000 kg.
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Fr = µr x n
F = ma
Max = F1 - F2
May = F1 - F2

## The Attempt at a Solution

To start off I drew a force diagram which showed thre forces; normal force going up, weight going down, and friction going in the opposite direction of the car. I found weight by multiplying the mass by 9.8, which ended up being 408200. I know that this must also be the amount for the normal force. But, now I'm at a standstill. I don't think the coefficients have anything to do with the problem but I'm starting to second guess myself. Am I able to use the mass and weight to figure out the decceleration of the car so that I will be able to use the velocity to find the distance? Thank you in advance!