Calculating Work and Kinetic Energy of Jet-Powered Train

AI Thread Summary
The discussion revolves around calculating the work done and kinetic energy of a jet-powered train from the 1950s, which has a mass of 2.5 x 10^4 kg and is propelled by a thrust of 5 x 10^5 N over 500 meters. Participants clarify that since the train starts from rest, the change in kinetic energy is indeed equal to the final kinetic energy. There is some confusion regarding the calculations for parts b and c, but it is confirmed that understanding the relationship between work and kinetic energy is crucial. The conversation highlights the importance of correctly interpreting the problem to avoid misunderstandings. Overall, the calculations are straightforward if the concepts are grasped properly.
DarkAnt
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In the 1950s, an experimental train that had a mass of 2.5 x 10^4kg was powered across level track by a jet engine that produced a thrust of 5 x 10^5N for a distance of 500m.
a) find the work done on the train.
b) find the change in kinetic energy.
c) find the final kinetic energy of the train if it started from rest.
d) find the final speed of the train if there was no friction.

ok, part A was easy. part b and c confuse me. since the train started at rest, wouldn't the change in kinetic energy be equal to the final kinetic energy?

am i missing something very important here or am i just missunderstanding this problem?
 
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Originally posted by DarkAnt
... since the train started at rest, wouldn't the change in kinetic energy be equal to the final kinetic energy?
Yes.
am i missing something very important here or am i just missunderstanding this problem?
That depends on whether you can answer the questions correctly or not. :smile: If the questions seem too easy... you're probably right.
 
thanks doc
 

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