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Homework Help: Energy/Work/Force HW question

  1. Jun 18, 2011 #1
    1. The problem statement, all variables and given/known data
    A force acting on an object moving along the x axis is given by Fx = 10x-2.0x2 N where x is in m. How much work is done by this force as the object moves from x = -1 to x= +6

    Distance = 7 m

    2. Relevant equations
    Work = Force * Distance cosine theta

    3. The attempt at a solution
    The equation for force is already given so I found force by integrating the equation Fx = 10x-2.0x2 to get Fx = 10-4.0x then I substituted the x for 7 to get -18 Joules. The problem I have is that the answer I got isn't among the options.
  2. jcsd
  3. Jun 18, 2011 #2
    You differentiated instead of integrated.
  4. Jun 18, 2011 #3


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    Homework Helper

    and Put the limits for x properly from -1 to +6, (Wx=+6 - Wx=-1)
  5. Jun 18, 2011 #4
    Oh, I see thanks.
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