Force problem (whoever answers correct will be rewarded a cookie )

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The discussion revolves around calculating the average force exerted by a train before its engine shuts down. The train has a mass of 6*10^5 kg and moves at a constant speed of 54 km/h, stopping in 40 seconds after the engine failure. Participants clarify that the problem requires finding the train's acceleration first, which can then be used to determine the force using the equation F=ma. There is confusion regarding the initial equation proposed, as it incorrectly combines concepts of force and power. The correct approach focuses on kinematics to solve for the average force.
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Homework Statement


Train with mass m=6*105kg moves with a constant speed of v=54km/h.After the engine shut down ,train stops in t=40s .Find the average force train performs before engine shut down?


Homework Equations


I think its asking for Force ? if yes will this equation below do ?


The Attempt at a Solution



F=m/t*(mv2/2)

I could be so wrong like GIGANTIC WRONG please braniacs reveal your wisdom on this very rough moment for me !
 
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What's F=m/t*(mv2/2)? Force certainly isn't equal to power times mass.

This is just a kinematics problem. Can you find the train's acceleration? If so, you can find the force using F=ma.
 
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