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I want to convert $~16~$in$^2$oz$^{-1}$ into cm$^2$ and grams. This is my attempt:

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I just want to check that my answer is correct, as my book says it should be $~3.686~$cm$^2$g$^{-1}$, but I got $~3.641~$.

I’m pretty sure this difference is due to a rounding error in the book, but just want to make sure, thanks!

nmasanta
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Jamminermit
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  • Google agrees with you. – lulu Aug 26 '19 at 16:41
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    Avoirdupois ounce or troy ounce? – user7530 Aug 26 '19 at 16:42
  • The OP's attempt clearly is using avoirdupois ounces given the 1 oz = 28.35g written in their work. Had it been a metric ounce, it would have ended up with $4.129~cm^2/g$. Had it been troy it would have been $3.319~cm^2/g$. I'm not going to bother with the other types of ounces... but it is worth noting that "ounce" by itself could be considered ambiguous. I strongly suspect it is a rounding error. – JMoravitz Aug 26 '19 at 16:46
  • @user7530 I don't know that! – Cameron Williams Aug 26 '19 at 16:52
  • To save people from having to look it up., avoirdupois ounces are those that are commonly used in USA to measure weight of food, people, etc... If you are thinking "16 ounces per pound" then you are thinking of avoirdupois ounces. Meanwhile, troy ounces are used to measure precious materials such as gold or gunpowder. They are mostly just used for historical reasons. – JMoravitz Aug 26 '19 at 17:36

1 Answers1

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Google search for

16 in^2/ounce in cm^2/gram

says 3.64118 so the rounding error is probably in the book. You should write the publisher or the author.

Ethan Bolker
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