How to Find the Final Speed of an Experimental Train?

AI Thread Summary
To find the work done on the experimental train, one must use the definition of work, which is the product of force and displacement. The train has a thrust of 4.63 × 10^5 N and travels a distance of 533 m. Therefore, the work done can be calculated by multiplying these two values. The discussion emphasizes that dividing force by mass yields acceleration, not work, and highlights the importance of understanding the correct formula for work. Ultimately, the solution involves a straightforward application of the work formula, reinforcing the concept that work is a function of force and displacement.
xlogit3k
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Homework Statement



In the 1950’s, an experimental train that had
a mass of 22500 kg was powered across a level
track by a jet engine that produced a thrust
of 4.63 × 105 N for a distance of 533 m.
Find the work done on the train.
Answer in units of J.


Homework Equations





The Attempt at a Solution



My attempted solution was to divide the force by the mass but this didnt work.
 
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xlogit3k said:
My attempted solution was to divide the force by the mass but this didnt work.
Dividing the force by the mass gives you the acceleration, not the work.

Knowing the acceleration, you could use kinematics to find the final velocity and then calculate kinetic energy. But there is a much easier way.

What is the very definition of work? (Hint: it's a function of force and displacement. :wink:)
 
collinsmark said:
Dividing the force by the mass gives you the acceleration, not the work.

Knowing the acceleration, you could use kinematics to find the final velocity and then calculate kinetic energy. But there is a much easier way.

What is the very definition of work? (Hint: it's a function of force and displacement. :wink:)

force x distance right?
 
xlogit3k said:
force x distance right?
That's right (well, technically the dot product of force and displacement). And the both force and displacement are given in the problem statement.
 
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