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Angular velocity Homework help

  1. Dec 31, 2006 #1
    1. The problem statement, all variables and given/known data
    "Many rivers, like hte Mississippi River, flow from north to south toward the equator. These rivers often carry a large amount of sediment that they deposit when entering the ocean. What effect does this redistribution of material have on the angular velocity of the earth? Why?"

    "A person is hanging motionless from a vertical rope over a swimming pool. She lets go of the rope drops straight down. After letting go, is it possible for her to curl into a ball and start spinning? Justify your answer."


    2. Relevant equations

    3. The attempt at a solution

    First, I am guessing that the question refers to the earth rotating about its axis, not revolving around the sun. If I am right on that part, would the effect be that it slows the angular velocity? The only reason I think that is the mass is moving farther away from the axis of rotation.

    My guess is no because initially she has no angular velocity, meaning that she has not angular momentem. Thus, even if the moment of inertia changes, she will still have zero angular momentum.
  2. jcsd
  3. Dec 31, 2006 #2


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    Correct, on both. For the first one, you might want to specifically mention the effect on the moment of inertia.
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