# Quick help on this

1. Oct 16, 2007

### azila

1. The problem statement, all variables and given/known data
One 105 kg football lineman is running to the right at 2.55 m/s while another is 130 kg lineman is running directly toward him at 2.80 m/s.

What is the total kinetic energy?

2. Relevant equations
ok, so K=1/2mv^2

3. The attempt at a solution

So, I found the kInetic energy for both of them and just added them together.
K1. K= (.50)(105kg)(2.55m/s)^2=341.38J

K2. K= (.50)(130kg)(-2.80m/s)^2=539.14J

So, I added them together and I got 880.52, which is not the answer and it keeps telling me that I have some sort of rounding error. Please help!!!!!!!!!!!!!!!!!!!1

2. Oct 16, 2007

### G01

If I am reading the question correctly, you are being asked for the total kinetic energy of both linemen. If this is correct, then I agree with your answer. Try putting the numbers in the calculator again and this time don't round off at all if you did before. (Computer homework systems can be a pain sometimes.)

3. Oct 16, 2007

### azila

i copied the wrong number when I was doing the calculations.. Thanks though.. I know I hate this Mastering Physics....