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Homework Help: Maximum kinetic energy

  1. Dec 15, 2008 #1
    1.the only force acting on a 2kg body as it moves along the x axis is given by F=(12-2x)N where x is in m. the velocity of the body at x=2m is 5.5i m/s. what is the maximum kinetic energy attained by the body?

    2. KE= mv^2

    3. My friend said the answer is 46J but im not sure how he got it
  2. jcsd
  3. Dec 15, 2008 #2
    Re: Helppp

    Looks like there's something wrong with this question.

    What is the force experienced by the mass at X=0?
    For what value of x does this force disappear?
    Does this force change in a linear fashion?
    If so, what's the average force on the mass?
    Now do we know the average force and the distance over which it operated?
    How much work was done?
    Can I equate this quantity of work to the kinetic energy received by the mass?

    What was the force at x=2m?
    What was the average force over the first two metres?
    How much work was done in the first two metres?
    What was the speed of the mass at two metres?
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