1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Quick help on this

  1. Oct 16, 2007 #1
    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. jcsd
  3. Oct 16, 2007 #2

    G01

    User Avatar
    Homework Helper
    Gold Member

    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.)
     
  4. Oct 16, 2007 #3
    i copied the wrong number when I was doing the calculations.. Thanks though.. I know I hate this Mastering Physics....
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Quick help on this
  1. Help quick (Replies: 2)

  2. Help quickly (Replies: 9)

  3. Quick Help! (Replies: 1)

  4. Quick Help! (Replies: 6)

Loading...