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Homework Help: Tension question

  1. Sep 12, 2005 #1
    A 6-kg of water is being pulled straight up by a string. The upward acceleration of the bucket is constant, with magnitude 3 m/s^2

    I need to find Tension. I have a problem getting the formula for this question. Can someone please help me? Thanks!
     
  2. jcsd
  3. Sep 12, 2005 #2

    Doc Al

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    The "formula" you need is Newton's 2nd law. To apply it, you'll need to identify the forces acting on the bucket of water.
     
  4. Sep 12, 2005 #3
    Is it F = T-mg=ma?
     
  5. Sep 12, 2005 #4

    Doc Al

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    Exactly right.
     
  6. Sep 12, 2005 #5
    Am I supposed to plug in -9.8 since gravity is pulling it down or 9.8 since the negetive is already in the formula for g?
     
  7. Sep 12, 2005 #6

    Doc Al

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    g = 9.8 m/s^2; the negative sign is already in the formula by putting the weight as "-mg".
     
  8. Sep 12, 2005 #7
    What if the acceleration is downwards? Would it be T = mg - ma?

    Does anyone know?
     
    Last edited: Sep 13, 2005
  9. Sep 13, 2005 #8

    Doc Al

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    That's correct.
     
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