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Homework Help: Resultant force help

  1. Feb 11, 2010 #1
    Missed a day of school due to a car accident in the blizzard and he went over resultant forces. Have this problem to due and I'm not quite sure on what I would do to solve this.

    http://img502.imageshack.us/img502/2087/blawu.jpg [Broken]

    add the three forces f1 f2 and f3 both analtically and graphically to find the resultant force r = f1 + f2 + f3 give the net force r in standard polar form.

    edit ; that is 45deg. by the way
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Feb 11, 2010 #2


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    Hi keith421, welcome to PF.
    Resolve f2 into vertical and horizontal components.T
    Then find ΣFx and ΣFy. Then find the resultant.
  4. Feb 11, 2010 #3


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    Try breaking f2 into its x and y components and then take ΣFx and ΣFy.

    Then put your answer into polar form by finding the magnitude of the resultant force and its direction.

    Edit: Too late...
  5. Feb 11, 2010 #4
    ok so i got the x and y component for F2, both 56.56.
    i then subtracted F1 10n from F2x 56.56 which i got 46.56
    then subtracted F3 30n from F2y 56.56 which got me 26.56

    then square root of 46.56²+26.56² = squartroot of c. which got me 53.6n.

    then did sin(26.56/53.6)= .4995. then sin-1(4.995)= 29.70.

    so 53.6 N and 29.70 NE. is this correct?

    what do i do for graphing?
  6. Feb 11, 2010 #5
    Last edited by a moderator: May 4, 2017
  7. Feb 11, 2010 #6


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  8. Feb 11, 2010 #7
    Thanks for the help, goodnight!
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