**1. The problem statement, all variables and given/known data**

A jet engine applies force of 300 N horizontally to the right against a 50 kg rocket. The force of air friction 200 N. If the rocket is thrust horizontally 2.0 m ,what is the kinetic energy gained by the rocket?

**2. Relevant equations**

I think these equations would be used:

f=ma

vf^2=vi^2+2ad

KE=1/2mv^2

**3. The attempt at a solution**

First I re-arranged the force formula and got a=f/m. Then I substituted (300-100)for f and 50 for m. I simplified it to 2.

Then I used vf^2=vi^2+2ad and substituted 0 for vi, 2 for a and 2.0 for d. Then I got 2.83 for vf.

Lastly, I used KE=1/2mv^2 and substituted 50 kg for m and 2.83 for v. My final answer is 200 J. I am not too sure if it is correct. Thanks in advanced!

**1. The problem statement, all variables and given/known data**

**2. Relevant equations**

**3. The attempt at a solution**

http://ift.tt/1fghyvz