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Homework Help: Pail homework problem

  1. Nov 27, 2005 #1
    a pail of water is rotated in a vertical circle of r=1.4m acceleration of gravity 9.8m/s^2

    the pail is rotated at a constant rate so it has the minimum speed at all points along its circular path. the water has a mass m.
    when the pail is at the bottom of the circle, what is the magnitude of the force exerted by the water on the bottom of the pail?

    F=ma=0 since it is at a constant rate right?

    but then i dont know what to do next?
     
  2. jcsd
  3. Nov 27, 2005 #2
    Nay! Draw out your free body diagrams, that should help.

    Also, I notice a lot of people making this mistake. Saying F = ma is rarely true. Always remember to add your sigma

    [tex]\sum F = ma[/tex]
     
  4. Nov 27, 2005 #3
    ?

    normal force is upward and weight is downward

    Fnet=Fn-mg?
     
  5. Nov 27, 2005 #4
    Help!!!!

    CAN ANYBODY HELP ME?!!!!!:cry:
     
  6. Nov 27, 2005 #5
    the water exerts two forces onto the pail... can you name them?
     
  7. Nov 27, 2005 #6
    :confused: its weight and........:confused:
     
  8. Nov 27, 2005 #7
    Centripital Force
     
  9. Nov 27, 2005 #8
    ....

    ok so its F=4mg or F=2mg?
     
  10. Nov 27, 2005 #9
    Centripital force is defined by equation:

    Fc = (m*v^2)/r
     
  11. Nov 27, 2005 #10
    gracias

    :uhh: thanks for everything but im just not understanding
     
  12. Nov 27, 2005 #11
    What is your current curriculum/topic in class?
     
  13. Nov 27, 2005 #12
    Dynamics Of Uniform Circular Motion
     
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