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Homework Help: Linear momentum

  1. Jan 15, 2007 #1
    I am not sure if I am doing this question right.

    A 10g bullet, traveling at 400 m/s hits a block of wood & emerges going at 350 m/s. How fast goes the block of wood move after being hit?

    Is this the right way to solve it?:

    mv of the bullet + mv of the block = mv' of the bullet + mv' of the block
    (.01)(400)+0=(.01)(350)+(2)v
    v=.25
     
  2. jcsd
  3. Jan 15, 2007 #2

    berkeman

    User Avatar

    Staff: Mentor

    You left the mass of the block out of your problem statement but included it in the work as 2kg (right?). Other than that it looks like a correct application of the conservation of linear momentum. Oh, and be sure to include units on the answer -- many folks (including me) will mark you down for leaving them off.
     
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