Equation 4.5-7

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Trevor Gore
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Re: Equation 4.5-7

Post by Trevor Gore » Wed Jul 27, 2016 9:09 am

Hello Miguel,

I'm guessing that you have the zero count wrong somewhere. (e. g. you have entered millimeters somewhere rather than 0.001 meters, or something similar, likely in more than one place).

If we take your 87.49mm number, divide it by SQRT(10) and then by 10 the answer is 2.77 mm which is in the ball park. Other than that, it's hard to say unless you email me your spreadsheet. My email address is on my website under Contact.

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kiwigeo
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Re: Equation 4.5-7

Post by kiwigeo » Wed Jul 27, 2016 11:43 am

Avoid wood with funny names scrawled on the wood in thick black texta pen and you'll be halfway there to ending up with some decent wood :mrgreen:
Martin

mqbernardo
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Re: Equation 4.5-7

Post by mqbernardo » Thu Jul 28, 2016 2:09 am

Thanks guys, so it appears i´m even more stupid than my ego would let me think... who´d have told? :)

Martin, i got lost somewhere in your kiwi humor...

Trevor, thanks for the help. I just emailed you my spreadsheet. As i told you in the mail it was made in open office and then exported to .xls format. I tried checking stuff again but couldn´t find where i had put mm instead of meters but this time i couldn´t even replicate the results using a calculator and a piece of paper...

Anyway, if you want i can also attach the file here in the forum, but maybe it´s against your book copyright?



once more, thanks!
Miguel

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Trevor Gore
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Re: Equation 4.5-7

Post by Trevor Gore » Thu Jul 28, 2016 9:22 am

Miguel,

I sent the corrected spreadsheet back to you. (A coding error and some "zero count" problems).
mqbernardo wrote:Anyway, if you want i can also attach the file here in the forum, but maybe it´s against your book copyright?
I prefer people to do their own coding on this so that they get a better understanding of what they're doing (rather than just downloading someone else's work). Most people seem to learn a lot from doing it themselves.

mqbernardo
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Re: Equation 4.5-7

Post by mqbernardo » Thu Jul 28, 2016 10:04 am

Thanks a lot Trevor! can´t wait to get back to the shop and check it. also curious to compare it with my own sheet and find where the errors lie.

you´re right, doing it yourself is often the best way to make sense of things. but a little help does go a long way! it was fun going through this stuff and trying to figure it out... up until a point! then it was just nerve wrecking...


Thanks again,
Miguel.

mqbernardo
Myrtle
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Re: Equation 4.5-7

Post by mqbernardo » Thu Jul 28, 2016 9:14 pm

OK, just compared your corrections with my original spreadsheet. While i could go on forever without knowing the SI units for MOE, i can´t believe i did the same error over and over with the divider on Eq 4.5-7... it´s really confusing me... anyway, values seem to be much closer to yours... close enough not to worry much about it.


thanks again!
Miguel.

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