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Partially inelastic collision

  1. Mar 25, 2007 #1
    1. The problem statement, all variables and given/known data

    Two identical objects, each moving at 1m/s but in oposite directions collide partially inelastically in one dimension. Assume the final total kinetic energy is half the intial total value. Calculate the final speed of each object

    2. Relevant equations

    This is my main problem. My book is written by my teacher and meant to compliment his notes, and i missed two days of class because of illness. There is actually NOTHING in the book about partially inelastic collisions, only completely inelastic collisions. If its possible that the completely inelastic equation must be modified it is:

    v' = (m1v1) + (m2v2)/(Total Mass)

    3. The attempt at a solution

    Dont even know where to begin...
  2. jcsd
  3. Mar 25, 2007 #2
    I believe what its saying that 2(1/2mV^2) is the initial energy of the system.

    after collision its saying that final energy (sums) of the two particles is 1/2 this, in other words 1/2MV1^2 and 1/2MV2^2=1/2(2(1/2MV^2). Its likely that the v1 and v2 are the same from other considerations, only maybe in different directions??
  4. Mar 25, 2007 #3
    ok well, the answer is actually given...i just need to know how it is solved, the answer that it gives is:

    .707m/s, .707m/s
  5. Mar 25, 2007 #4
    well from conservation of mo, one should be -0.707m/s, the .707 which can be derived from eqn as I posted above or at a glance knowing from cons of mo, and that final total energy =1/2 initial energy,
    (1/2MVi^2)=2(1/2mvf^2). vf/vi=1/sqrt(2)
  6. Mar 25, 2007 #5
    vf/vi=1/sqrt(2) is what i should actually be using? What am i solving for in this equation....and the answer specifically states that they are both .707, one isnt negative.
  7. Mar 25, 2007 #6
    ok now i understand everything u said and i know how to do it now.

    And i would like to add that this website is the most help i have ever recieved from any source. Ive gone to study sessions at the math lounge at my college and sought help from other students in my class and this site beats all of that put together. Thanks so much for your help!
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