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Physics Help Pleaase

  1. Feb 22, 2007 #1
    Physics Help!! Pleaase

    1. The problem statement, all variables and given/known data

    A mass, m, traveling at a speed v, strikes another mass = 2m at rest. After the collision, the first mass, m, is delfected through 45 degrees and has a final speed of v/2.
    Find the speed and Direction of the mass 2m after this collision.

    2. Relevant equations
    p =mv

    3. The attempt at a solution

    2mfsinT = -mv/2sin 45
    mv+2m+ 0 - mv xdr
    mv = mv/2cos45+2mfcosT

    Anyone help ..
  2. jcsd
  3. Feb 22, 2007 #2


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    Homework Helper

    I'm guessing you are trying to use conservation of momentum. What is f? What is xdr? Why do you only have a 2m there in the second line? Actually, that second line isn't even an equation! You need to start by drawing a diagram and breaking it up into x and y components, before the collision and after.
  4. Feb 22, 2007 #3
    I have
    let theta of missing angle = x
    v2 = velocity of second mass , 2m
    cos45mv/2 + cosX = mv
    sin45mv/w= sin X 2Mv2
    I can't solve it now..
  5. Feb 23, 2007 #4


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    Homework Helper

    "cos45mv/2 + cosX = mv"

    There should be a term for the velocity of the 2m mass in front of the cosX.

    "sin45mv/w= sin X 2Mv2"

    I'm assuming the w is really a 2??

    Everything looks OK I think. You have two equations and two unknowns (not counting the v that is the initial velocity). So put the second equation in terms of one of the unknowns and plug it into the first equation. Solve for that unknown.
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