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Tension in cord, No mass

  1. Oct 18, 2009 #1
    1. The problem statement, all variables and given/known data
    While in a car, a rubber ball is suspended by a cord. When the car slows down, the ball forms a 13 degree angle. Find the acceleration of the car when it is slowing down and the tension in the cord.
    I found the acceleration of the car, which is 2.3 m/s2 easily but when i try to find the tension, i am left with the unknown on the numerator of both sides of the equation and i can`t go further.
    2. Relevant equations
    In Y
    T*cos x=mg
    In x
    what do i do now?
    3. The attempt at a solution
    see above
    Last edited: Oct 18, 2009
  2. jcsd
  3. Oct 18, 2009 #2

    Doc Al

    User Avatar

    Staff: Mentor

    You won't be able to solve for the tension without knowing the mass of the ball.
  4. Oct 18, 2009 #3
    i thought so too because the question asks you if it is actually possible to find the tension without the mass. I answered no but in the book`s answer key, there`s actually an answer (it`s 0.25N).
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