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Homework Help: Astronaut in rotating space station

  1. May 11, 2010 #1

    bon

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    1. The problem statement, all variables and given/known data

    cylindrical space station - large diameter, thin walled - radius r, mass M rotating in deep space, no gravity

    1)radial spokes of negligible mass connect the cylinder ti the centre of motion. Astronaut mass m climbs a spoke to the centre. What is the fractional change in apparent gravity on the surface of the cylinder?

    2)if the astronaut climbs halfway up a spoke and lets go, how far form the base of the spoke will he hit the cylinder? Assume the astronaut is point like..

    2. Relevant equations



    3. The attempt at a solution

    1) Got the answer to be 1+m/M for ratio after/before..

    is this right? I applied conservation of energy rather than angular momentum...why is angular momentum not conserved?

    2) How do i do this one? Consv of energy again?
     
  2. jcsd
  3. May 11, 2010 #2

    bon

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    anyone?
     
  4. May 12, 2010 #3

    bon

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    Anyone able to help with this please? :)
     
  5. May 12, 2010 #4

    bon

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    *bump*
     
  6. May 12, 2010 #5

    ehild

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    Homework Helper

    You forgot to show your work again. :)

    ehild
     
  7. May 12, 2010 #6

    bon

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    Ok I didn't show because I'm just wanted to ask the following question first:

    In the two cases, it is ENERGY rather than ANGULAR MOMENTUM that is conserved - yes? Why is angular momentum not conserved?
     
  8. May 12, 2010 #7

    bon

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    any ideas?
     
  9. May 12, 2010 #8

    ehild

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    The angular momentum of the whole space-station+ astronaut is conserved, as there is no external torque.

    ehild
     
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