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Homework Help: Use Force, Mass and Acceleration to find velocity

  1. Oct 1, 2011 #1
    1. The problem statement, all variables and given/known data
    A 2 kg block initially at rest is pulled to the
    right along a horizontal, frictionless surface
    by a constant, horizontal force of 13.4 N.
    Find the speed of the block after it has
    moved 2.4 m.
    Answer in units of m/s


    2. Relevant equations
    F=MA
    V=Vo + at
    X=1/2 at2


    3. The attempt at a solution
    13.4/2=6.7
    time=.716417
    velocity=4.79989
     
  2. jcsd
  3. Oct 1, 2011 #2

    gneill

    User Avatar

    Staff: Mentor

    Hi trivk96, Welcome to Physics Forums.

    Your time and velocity don't look right. Can you post your work?
     
  4. Oct 1, 2011 #3
    This is another try. Can you check if this is right


    F=ma
    13.4=2a
    a=6.7

    V=6.7t

    x=1/2at2
    2.4=.5(6.7)t2

    t2=.7164
    t=.84641

    V=6.7(.85641)
    V=5.570978
     
  5. Oct 1, 2011 #4

    gneill

    User Avatar

    Staff: Mentor

    The method looks fine. I think you made a typo transcribing your time value into the final calculation, so the velocity is a bit off. Check it out.

    Try using the x2 icon in the reply panel header to incorporate exponents in your posts.
     
  6. Oct 1, 2011 #5
    Thank You
     
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