Find Distance Given Mass and Velocity for Failed Locomotive

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To determine how far a 50,000 kg locomotive traveling at 10 m/s will roll after both its brakes and engine fail, the key factor is the deceleration due to friction, which is not provided in the problem. Participants in the discussion emphasize the need for a coefficient of friction to calculate deceleration, as without it, the distance cannot be accurately determined. Some suggest that the locomotive would continue moving unless a resistive force is applied. The textbook answer of 2550 m is mentioned, but participants express confusion over how to arrive at that figure without friction data. Overall, the consensus is that additional information about friction is essential for solving the problem.
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If a 50 000 kg locomotive is traveling at 10m/s and its brakes and engine both fail, how far will it roll before coming to a stop.

Now I know how to do this problem if friction was given but I really don't know which formulas i can combine.

I think I need to find deceleration but I don't know how with the information given.

If someone could give me a hint how to get started it would be appreciated:)
 
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Are you sure that is all the question gave? Because if you ignore friction, then there must be some other force acting on the train, else by Newton's first law, that train should continue to move in a straight line.
 
sorry man, there is no way to find this..because we need to find the deceleration..which is either
a. negative acceleration because of engine
b. negative acceleration because of friction

we know that it's v=10ms-1, but we don't know a time or accel
 
i know, if there was friction i could use ma=mgUs and find acceleration to sub into a kinematics formula to find d skidding

the question oly gives what i wrote above
 
my textbook gives the answer as 2550m
 
krisrai said:
If a 50 000 kg locomotive is traveling at 10m/s and its brakes and engine both fail, how far will it roll before coming to a stop.

Now I know how to do this problem if friction was given but I really don't know which formulas i can combine.

I think I need to find deceleration but I don't know how with the information given.

If someone could give me a hint how to get started it would be appreciated:)

I think you can assume the engine is running constantly, providing a force to push the train. But the train is not accelerating, it is traveling at 10 m/s. When the engine fails, the resistive force that keeps the train traveling at 10 m/s is the only force remaining, since the brakes also fail.

Sheldon
 
definitely helps thank you hage
I just wasnt expecting that i would have to look up the coefficient of rolling friction like pingpong did.
 
Yeah, I agree that's a bit strange.
 
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