Stress calculations

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Stress calculations

Postby Jerry Attrick » Sat Feb 16, 2008 5:15 pm

I used to have a PPL, now grounded due health.
Current interest is large R/C aircraft, and I'm working on designing a large model from scratch.  To that end I'm reading "Stress without tears" by Tom Rhodes.  If anybody is familiar with the book could you please tell me whether his answer to the problem set in chapter one (i.e. 27 lbs) is correct.  I get 25 lbs and fail to see his logic for his answer.

HELP PLEASE, anybody.
Jerry Attrick
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Postby Jerry Attrick » Sun Jan 03, 2010 9:40 pm

Having reconsidered the whole thing, and looked at your working, Dan, I can't imagine where I got 25lb from.  I follow your working perfectly, and of course agree with it.  So now I'm feeling foolish.  Even using the 200 instead of the 204 only makes a difference of 0.55 in the final answer.  In mitigation my original query is nearly a year old  -  so perhaps I've gained wisdom since then!!??

So I thank you for your interets and help, wish you a happy and successful New Year, and I think quietly close the book on this one.

Sincerely,
Jerry
Jerry Attrick
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Posts: 2
Joined: Sat Feb 16, 2008 5:03 pm
Location: New Zealand


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