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Homework Help: Determine the magnitude and direction of smallest force

  1. Jan 6, 2012 #1
    1. The problem statement, all variables and given/known data

    To move the oil drum, the resultant of the three forces shown must have
    a magnitude of 500 N. Determine the magnitude and direction of the smallest
    force F that would cause the drum to move.

    here is the figure: http://screensnapr.com/e/yliMVN.png [Broken]

    2. Relevant equations

    summation of x forces = 0 - 300 * cos25 + F cos (p)
    summation of y forces = 250 - 300 * sin 25 + F sin (p)

    3. The attempt at a solution

    i tried using those 2 equations and put it in

    R ^2 = x ^2 + y ^2 (phytagorean theorem for resultant)

    but i ended with 2 variables missing which is F (magnitude) and p(direction). Any insights? Thanks
     
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Jan 6, 2012 #2
    Take the two forces given and combine them to give a single net force, draw that in and you should be able to find a direction which uses your force the most efficiently :)
     
  4. Jan 6, 2012 #3
    when we say most efficiently? u pertain that it has to be in the same direction as the resultant?
     
  5. Jan 6, 2012 #4

    BruceW

    User Avatar
    Homework Helper

    yep, you got it.
     
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