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Homework Help: What force, in newtons, does the wood exert on the bullet?

  1. Sep 15, 2004 #1
    A .22 rifle bullet, traveling at 350 m/s, strikes a block of soft wood, which it penetrates to a depth of 0.130 m. The block of wood is clamped in place and doesn't move. The mass of the bullet is 1.80 g. Assume a constant retarding force.

    1.) What force, in newtons, does the wood exert on the bullet?

    using Newton's Second Law (F=ma)

    first i had to find a
    v^2f = V(0)^2 + 2ax <--- equation of motion
    0=350^2+2(a)(0.130)
    a = 471153.8462

    then plug in known values for newton's second law

    F = (1.80)(471153.8462) = 848076 N
    or 8.48×10^5 N

    but it's the wrong answer, can someone help?
     
    Last edited: Sep 15, 2004
  2. jcsd
  3. Sep 15, 2004 #2
    You've not converted your mass to kilograms.
     
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