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Timeline for Balancing a pencil

Current License: CC BY-SA 3.0

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Mar 1, 2015 at 5:57 vote accept Dhruva Patil
Feb 28, 2015 at 21:07 history edited hft CC BY-SA 3.0
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Feb 28, 2015 at 21:07 comment added hft Yes, I=m(l/2)^2 for a bob on string of length (l/2). Thanks for the correction.
Feb 28, 2015 at 20:24 vote accept Dhruva Patil
Mar 1, 2015 at 5:57
Feb 28, 2015 at 20:21 comment added Dhruva Patil Alright, that makes sense. Thank you. And also, the last edit you made, shouldn't it be divide by 4 instead of 2?
Feb 28, 2015 at 20:17 comment added Dhruva Patil So, the L is really the length of the hypothetical pendulum you are replacing the pencil with?
Feb 28, 2015 at 20:12 comment added hft In those links "l" is the length of the pendulum.
Feb 28, 2015 at 20:09 comment added Dhruva Patil Shouldn't it be $\frac{ml^2}{4}$?
Feb 28, 2015 at 20:08 comment added hft The first link does exactly what I said at the bottom of my post. It models the pencil as an "inverted pendulum". I.e., a bob at the center of mass, which is ignoring the fact that it is actually a solid rod.
Feb 28, 2015 at 20:06 comment added Dhruva Patil The answer, all over the internet, seems to be the one in the question. Links: thatsmaths.com/2014/06/26/balancing-a-pencil, youtube.com/watch?v=U3vAoJhIWms#t=29, arxiv.org/pdf/1406.1125v1.pdf
Feb 28, 2015 at 20:04 history edited hft CC BY-SA 3.0
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Feb 28, 2015 at 19:58 history answered hft CC BY-SA 3.0