1. Limited time only! Sign up for a free 30min personal 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!

Energy and mass

  1. Feb 27, 2008 #1
    1. The problem statement, all variables and given/known data
    A ball of mass m = 56 g is shot with speed vi = 20 m/s (in the negative direction of an x axis) into the barrel of a spring gun of mass M = 222 g initially at rest on a frictionless surface. The ball sticks in the barrel at the point of maximum compression of the spring. Assume that the increase in thermal energy due to friction between the ball and the barrel is negligible. What fraction of the initial kinetic energy of the ball is stored in the spring?

    2. Relevant equations

    3. The attempt at a solution
    I found the final velocity to be -4.03 m/s by using m1v1=(m1+m2)v2 and got v2 to be -4.03m/s. From here I am kind of stuck. It means that its stored as potential energy...so U=Ki-Kf and I have Ki as 0 and Kf as 2257.49. Would i take the potential divided by the Kinetic?
  2. jcsd
  3. Feb 27, 2008 #2
    your on the right tracks
  4. Feb 27, 2008 #3
    but if you take the potential divided by kinetic, you get division by 0
  5. Feb 27, 2008 #4
    still stumped
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Energy and mass
  1. Mass/energy problem (Replies: 9)