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Homework Help: Picture attatched. help find tension?

  1. Nov 21, 2011 #1
    1. The problem statement, all variables and given/known data

    What is the tension T in the string?

    2. Relevant equations

    Is their an equation for tension. not in my book?
    3. The attempt at a solution
    im soo lost.

    Attached Files:

  2. jcsd
  3. Nov 21, 2011 #2
    Start with a Free Body Diagram

    The only formula you will ever need is F = ma, and some trig skills
  4. Nov 21, 2011 #3
    i think the forces are gravity, tension and frictional.
  5. Nov 21, 2011 #4
    wait no theres surface
  6. Nov 21, 2011 #5
    What do you mean you "think" there is friction? That's actually important...
  7. Nov 21, 2011 #6
    um because its touching the surface
  8. Nov 21, 2011 #7
    Does the problem state there is friction? We don't want to add anything we don't want
  9. Nov 21, 2011 #8
    it says " the coefficients of kinetic friction and static friction between the left hand box and the plane are .15 and .30"
  10. Nov 21, 2011 #9
    Wellllllllll wouldn't that be great if you told us that from the start?

    You still haven't provided us a Free Body Diagram. It's good you know what forces are present, but what forces are acting on each body?
  11. Nov 21, 2011 #10
    heres my force diagram.

    Attached Files:

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