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Homework Help: Cylindrical centrifuge filled with water.What happens first spills or bottom visible.

  1. Sep 18, 2008 #1
    1. The problem statement, all variables and given/known data

    A cylindrical centrifuge of raidus 1 m and height 2 m is filled with water to a depth of 1 meter. As the centrifuge accelerates, the water level rises along the wall and drops in the center; the crossection will be a parabola.

    a) Find the equation of the parabola in the figure in terms of h, the depth of the water at its lowest point.

    b) As the centrifuge rotates faster and faster, either water will be spilled out of the top, or the bottom of the centrifuge will be exposed. Which happens first?

    2. Relevant equations

    depth of water= 1m

    3. The attempt at a solution

    I've been thinking this problem must have something to do with integrals, but i am lost in the fact that the parabola from the cross section is constantly growing. I just can't seem to find an equation for the parabola, but i have made a hypothesis that the bottom will be exposed first, based of course off of no mathmatical basis. Help desperately needed.
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Sep 19, 2008 #2


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    Last edited by a moderator: Apr 23, 2017
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