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Homework Help: FORMULA CALCULATION PROBLEM about FORCE

  1. Oct 21, 2011 #1
    1. The problem statement, all variables and given/known data
    1.)I can't get it why a friend of mine from this forum is getting 56.01N and me 56.70N
    2.) I got this solution 50Ncos30-(0.02(20(9.8)-50sin30))/20, what did you get??
    3.) (0.4(20x9.8))/cos30+(0.4(sin30)) what did you get?
    2. Relevant equations
    1)F= (0.1(50x9.8))/(cos25 - (0.1sin25))
    2)50Ncos30-(0.02(20(9.8)-50sin30))/20
    3) (0.4(20x9.8))/cos30+(0.4(sin30)) what did you get?

    3. The attempt at a solution
    1)F= (0.1(50x9.8))/(cos25 - (0.1sin25)) =56.70N

    and my friend got 56.01N???

    2) 50Ncos30-(0.02(20(9.8)-50sin30))/20=1.99m/s^2
    3) (0.4(20x9.8))/cos30+(0.4(sin30))= 73.5N

    all I'm asking is your answers on this following formula..
     
  2. jcsd
  3. Oct 21, 2011 #2

    Delphi51

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    Homework Helper

    I agree.
    It would be interesting to try the calc with calculator on radians and see if you get 56.01.
     
  4. Oct 21, 2011 #3
    so you agree with me? that my answer is correct?? 56.70N? how about the other equations? what did you get?
     
  5. Oct 22, 2011 #4

    I like Serena

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    Let's see:
    2) 50Ncos30-(0.02(20(9.8)-50sin30))/20 = 43.1
    3) (0.4(20x9.8))/cos30+(0.4(sin30)) = 90.7

    I see a mismatch...

    But, seeing the structure of your formula, I suspect you need:
    2) (50Ncos30-0.02(20(9.8)-50sin30))/20 = 1.99
     
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