1. Dec 29, 2007

### eagles_reciever

i am trying to solve this problem:

In the 1950s, an experimental train that had a mass of 2.60 X 10^4 kg was powered across a level track by a jet engine that produced a thrust of 5.25 X 10^5 N for a distance of 509 m. Assume that air resistance is negligible.

i am trying to find out the change in kinetic energy of the train and the final kinetic energy. however i cannot figure out what the velocity of the train is. Can anyone help please or provided an equation??

Thank you

2. Dec 29, 2007

### arildno

You don't need it.
You are to find the CHANGE in the kinetic energy; that can be calculated by the work done by the force given.

3. Dec 29, 2007

### eagles_reciever

im not understanding.. so find the change in work???

4. Dec 29, 2007

### eagles_reciever

Speed equation?

how would i find the speed of the train in this problem:

In the 1950s, an experimental train that had a mass of 2.60 104 kg was powered across a level track by a jet engine that produced a thrust of 5.25 105 N for a distance of 509 m. Assume that air resistance is negligible.

The equation is d/t but i do not know what the time is. can anyone help please????

Last edited by a moderator: Dec 29, 2007
5. Dec 29, 2007

### Staff: Mentor

6. Dec 29, 2007

### Erythro73

If I assume the acceleration to be uniform, I would suggest to use the kinematic equation :
$V_{f}^{2}=V_{i}^{2}+2*a*d$

as you know d and a.

7. Dec 29, 2007

### arildno

No, force times distance equals change in kinetic energy.