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nayukitoday at 6:49 PM1 replyview on HN

Upvoted, and the English prose is pretty good in spelling and grammar, but the metric units in the writing need improvement.

> 10 microns

"Micron(s)" is a deprecated word since 1967 and "micrometre(s)" must be used instead. The reason is that it is a non-standard word; if "micron" is accepted, then we should also accept the nonsensical words "millin", "nanon", "kilon", etc. The metric system is supposed to be easy to learn with consistent rules and as few special cases as possible.

> 4.8mm ... 0.01mm ... "0.002mm tolerance"

These numbers are correct, but it's harder to quickly skim the text and make comparisons because the number of decimal places vary. It would be better to write 4.800 mm, 0.010 mm, 0.002 mm to make the reader's job easier. Or convert everything to whole micrometres, like 4800 μm, 10 μm, 2 μm.

> withstand over 4,000 Newtons

Almost correct, but the unit must be decapitalized to "newtons". This is similar to how other name-based units are decapitalized - like "100-watt light bulb", "12 amps", "3 gigahertz".

> 2-3 Newton insertion force

It must be written as "2–3 newtons". When the unit name is written out in full, it follows normal English pluralization rules (e.g. metres, seconds, volts, pascals, kelvins, ohms, teslas). The only exceptions are hertz and siemens, because they already end with -s or -z.


Replies

jjk166today at 7:01 PM

This is why we measure things in baby elephants per football field.