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So... I'm wondering what the measurement of an AMU (atomic mass unit) is... I mean.. I've heard it's really the weight of a proton but then I'm told the proton's weight is actually 1.0073 amu.. so what is the amu based on then?

btw: how do you pronounce a decimal number such as ... .0007 or .0000009?

Thanks.

ALSO...

I was reviewing diff temp conversion and the "formulas" for them... I noticed something that kind of made me stop for a second...

(F - 32ºF) x (5ºC/9ºF) = C

Now.. knowing how both temps are the same at -40º, I worked it out and it doesnt quite work when it's done like this:

-40 - 32 = -72

now take 5/9 = .555555etc...

that means it cant possibly be -40 but instead around 39.999 or something...

Now.. if you instead cross multiple and simplify the 72 into an 8 and the 9 into a 1 then you get:

-8 x 5/1 = -40

My problem clearly is mathematical... so I'm wondering what I'm doing wrong.. and why with the two "valid" methods there is a difference, small but there's one.

I hope it's not some theory of how .999999999999999999999 is technically one.

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# Question about AMU & Temp. Conversions

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