Question - Universal Speed Limit

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The discussion revolves around the concept of angular acceleration in a long cylinder and whether the effects of torque applied at one end would take a year to reach the other end, in line with the universal speed limit of light. Participants acknowledge the challenge of visualizing rotational motion and suggest that thinking in terms of a rope could simplify the understanding of the problem. The conversation also touches on personal experiences in Bemidji, Minnesota, and the local lakes, with a mention of potential academic transfers to nearby universities due to staffing issues at the local physics department. Additionally, there are considerations about the benefits of attending the University of North Dakota over the University of Minnesota, including cost and student-to-teacher ratios. Overall, the thread combines physics inquiry with personal anecdotes and academic advice.
Zarathustra1
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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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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.)
 
Integral said:
https://www.physicsforums.com/showthread.php?t=98696" asks a similar question. The answer is the same.

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.

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.)

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.
 
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Zarathustra said:
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

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).

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.

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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