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 lost during collision

  1. May 22, 2009 #1
    1. The problem statement, all variables and given/known data

    A 40.8 g ball of clay hits and sticks to a 3.41 kg block sitting at rest on a frictionless surface. What is the speed of the block after the collision if the initial speed of the ball of clay is 5.04 m/s?
    b)What percentage of the system's initial energy is lost?

    2. Relevant equations

    pinitial=pfinal, E=0.5mv2

    3. The attempt at a solution

    for the first part i figured out the speed final which is 0.0596 m/s
    for the second part for each i figured the initial energy and then the final energy using the energy equation for both objects involved. after this part i am stuck to figure out the energy lost i came up with this equation 100-(Einitial-Efinal/Efinal) x100.. i used it and am not getting the right answer..pls. help
     
  2. jcsd
  3. May 22, 2009 #2

    diazona

    User Avatar
    Homework Helper

    Divide by initial energy, not final energy (that's what it means by "percentage of the initial energy").
     
  4. May 22, 2009 #3
    thanks :)
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook