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Question - Universal Speed Limit

  1. Nov 14, 2005 #1
    I understand that nothing--object or influence--can travel faster than c. However, something isn't quite clear to me.

    Let's assume we have a solid rod or a cylinder that has any given radius and a light-year in length. If the cylinder is at first at rest, and then we apply a torque to this cylinder at one end, thus giving it angular acceleration, will it take a year for the other end of the cylinder to experience the angular acceleration?
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  3. Nov 14, 2005 #2


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    Last edited by a moderator: Apr 21, 2017
  4. Nov 14, 2005 #3


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    however, Zarathustra, Bemdji MN is a cool place. welcome! (have you ever swam or skied in Bad Medicine Lake, a little south of you? i had 30 years ago and thought it was wonderful.)
  5. Nov 15, 2005 #4
    Doh, I've been thinking too much about rotational motion lately. Thinking about it in terms of a rope would have been much more convenient in allowing me to answer the question myself.

    Nope, can't say I've been to that lake (so many lakes around here it's hard to keep track of them all!). Bemidji is dandy indeed, though the BSU physics department is rather under-staffed, so I might end up going down to the twin cities and transfer to the University of Minnesota. Dunno yet though.
    Last edited by a moderator: Apr 21, 2017
  6. Nov 15, 2005 #5


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    not that many as clean as Bad Medicine Lake. it's on MN 113 west of uh.. what's that lake that is the source of the Mississippi? i don't remember the name (but somehow i remember this road, oh... it's Itasca).

    consider UND in Grand Forks (my alma). you have reciprocity and it'll be cheaper than UM. caveat, it's colder than a sorceress's bosum there (but it must also be in Bemidji) in January/February. also much better student to teacher ratio. cheaper housing. but more boring social life. and too many republicans and religious right, but not as bad as the western part of the state.
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