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1998 Physics B Rainstick Problem (Help)

  1. Oct 18, 2009 #1

    Students are designing an experiment to demonstrate the conversion of mechanical energy to thermal energy. They have designed the apparatus shown above. Small Lead Beads of a total mass M and the specific heat c fill the lower hollow sphere. The valves between spheres and the hollow tube can be opened or closed to control the flow of the lead beads. Initially both valves are open.

    A) The lower valve is closed and the student turns the apparatus 180 γ about the horizontal axis, so that the filled sphere is now on top. This elevates the center of mass of the lead beads by a vertical distance h. What minimum amount of work must the student do to accomplish this?

    U= Q-W

    I honestly have no idea where to start. The lack of actual measurements threw me off so I appreciate any help.
    Last edited: Oct 18, 2009
  2. jcsd
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