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Homework Help: Force related to distance question

  1. May 28, 2013 #1


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    1. The problem statement, all variables and given/known data
    So I have worked through most of the problem and what I have so far is correct. Basically, I have force as a function of time which, when exerted on an object, moves the object up a 15 degree slant. Given two points in times, my question reduces to finding the total distance traveled within this time period. It should be known I have initial and final velocities.

    2. Relevant equations
    work/energy seems useful here [itex]U=\Delta V_G + \Delta T[/itex]

    i don't think i need impulse, or namely [itex]\int \sum F dt= \Delta G[/itex] as this deals explicitly with time, which I have already used to get the force function (though I could be wrong)

    3. The attempt at a solution
    I was thinking [itex]U=\int F ds = m g sin(15) s + m {{V_2}^2}/2 - m {{V_1}^2}/2[/itex] where [itex]s[/itex] is the distance travelled I am looking for and the force function [itex]F[/itex] is changed to only account for forces other than gravity (since the [itex] \Delta V_G[/itex] term accounts for potential gravity.

    but then, since [itex]F[/itex] is a function of time, i'm not sure how to proceed (if you need the force function I can give it, but it's kind of long)

    I know both initial and final velocities [itex]V_1 , V_2[/itex]

    Any ideas would be helpful! Thanks!
    Last edited: May 28, 2013
  2. jcsd
  3. May 28, 2013 #2
    I would think that given F(t), and the mass, you would integrate a(t) to find v(t) and then again to find d(t) distance a function of time. When you integrate a(t) you have the initial velocity given. Does the force act parallel to the plane?
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