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Tension of rope problem

  1. Feb 5, 2008 #1
    A mountain climber, in the process of crossing between two cliffs by a rope, pauses to rest. She weighs 565 N. As the drawing shows, she is closer to the left cliff than to the right cliff, with the result that the tensions in the left and right sides of the rope are not the same. Find the tensions in the rope (a) to the left and (b) to the right of the mountain climber.

    Im sorry but i really dont know where to start.

    angle on 1st is 65
    angle on 2nd is 80

    Attached Files:

  2. jcsd
  3. Feb 5, 2008 #2
    If she weighs 565N that is how much gravity is pulling down on her, what is pulling her back up to keep her from falling?
  4. Feb 5, 2008 #3
    Normal Force, but isnt it the same as the 565 N.
    How is the brought to tension
  5. Feb 5, 2008 #4
    the normal force is right, which would act straight up, but is there anything holding her straight up?
  6. Feb 5, 2008 #5
    the tension on the rope is the only thing i can think of.
  7. Feb 5, 2008 #6
    right, that is the only thing holding here up. now how are you going to turn a vertical force into one that is almost perpendicular?
  8. Feb 5, 2008 #7
    I am really not sure, this is where i am lost
  9. Feb 5, 2008 #8
    hint: the answer is in the angles
  10. Feb 5, 2008 #9
    also, I wish your picture would work so I could see the problem, that would help
  11. Feb 5, 2008 #10
  12. Feb 5, 2008 #11
    The only thing I can think of is taking the sin of the angles to get the vertical force, but how do i relate this.
  13. Feb 5, 2008 #12
    no, it does not. but depending on where the angles are, you are going to use sin or cos to figure out your 2 tensions
  14. Feb 5, 2008 #13
    \ (65)................ - (80)
    .\.............. -
    ...\ ..... -
    .....\ -

    best picture i can make sorry.

    person is hanging in between with a 65 degree angle on left and 80 degrees on right.
    Last edited: Feb 5, 2008
  15. Feb 5, 2008 #14
    hold on that didnt post correctly

    ok the .....'s are empty space, needed it to make space.

    the \\\\\'s are the rope being pulled 65 degrees
    the ---'s are rope being pulled 80 degrees

    sorry, best i can come up with
    Last edited: Feb 5, 2008
  16. Feb 5, 2008 #15
    does the problem look like this?

    A --------- c ----------------- B

    ---------- D

    AB would be the rope, D would be the climber, 80* would be the angle between Dc and DB, and 65* would be the angle between Dc and DA?
    Last edited: Feb 5, 2008
  17. Feb 5, 2008 #16
    close, the 80* is the angle on the outside of DB, 65* is outside DA

  18. Feb 5, 2008 #17
    so are the angles

    \ 65*...|....80*/
  19. Feb 5, 2008 #18
    got it, ok
  20. Feb 5, 2008 #19
    Yes.., the outside angles
  21. Feb 5, 2008 #20
    you don't need to figure out the vertical component of force, you should know that. What is the vertical component of force in Newtons?
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