1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

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

  5. Nov 27, 2005 #4

    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

    :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
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook