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Hard Torque question I can't seem to understand !!
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http://img337.imageshack.us/my.php?image=lastscanno5.jpg I have no clue how to start this. Where should I place the pivot point ?!?! How does it even start ?!?!? THANK YOU SO MUCH! |
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Re: Hard Torque question I can't seem to understand !!
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by
on 2007-05-21 22:26:44 |
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You want to maximize X, right? The top book can be, at most, offset by 0.5L from the book below. The two books together have length 1.5L (2L minus the 0.5 overlapping). The x-axis center of mass is at 0.75L (1.5L/2, right in the middle). The projection from the table, X, is then 0.75L (half the weight hangs off the table). In order to get 1.0L off the table, you need at least 3 books (since we saw from the previous question that 2 isn't enough). It can easily be done with three books, each covering 50% of the below book, with the bottom book placed at the edge of the table. The top book will be 100% over the edge, the bottom book 100% on the table, and the middle book 50% over the table, for a center of mass at the table's edge. Don't let you're cat near the books, she'll nock them over. Cat's are evil that way. Cute, but evil. 
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Re: Hard Torque question I can't seem to understand !!
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No. If you can't get one book off the table with two books, you can never get it off the table on the full length of L, since the book at the edge can be considered a table itself. Illustration (sorry for my bad drawing skills): http://s27.photobucket.com/albums/c182/kimusabi/?action=view¤t=untitled-2.jpg
~roll away!
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Re: Hard Torque question I can't seem to understand !!
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by
on 2007-07-08 23:20:22 |
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you're right, it takes 4.
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