4 ms·
A few micrometers in size. I dont think in micrometers, so I must convert to a more familiar unit. A few .001mm in size. That's tiny. An average piece of paper
by loonster 5y ago
A few micrometers in size. I dont think in micrometers, so I must convert to a more familiar unit. A few .001mm in size. That's tiny. An average piece of paper is .1mm thick. This is around the size of the thickness of ink on the paper.
- COGlory 5y ago30 or so coronaviruses side by side.
- abduhl 5y agoA few micrometers is around 1E-4 inches or 3E-6 yards for those of us who think in freedom units (aka real units).
- JshWright 5y agoYou joke, but this would (perhaps even more absurdly, really) be called a "tenth" by most people who care about imperial units at this scale (as explained in a sibling comment)
- version_five 5y agoThis is pretty anti-intellectual isn't it? People, in my opinion rightly, make fun of measures expressed in libraries of congress or Olympic pools or African elephants, and then an article actually uses a normal SI measure and that gets disparaged too? What are authors supposed to do?
- sgc 5y agoThere was nothing disparaging about the comment. There is also nothing anti-intellectual about comparing things you don't know to things you do, in order to contextualize information. And he did that by first converting to mm, so did not abandon SI measurements at all. I agree that when we are talking about more common measurements it can be gratuitous or grandstanding, much like talking about things over 1x size in percent, as e.g. 450% bigger, etc. But that is not the case here.
- JshWright 5y agoYeah, for folks with experience in machining (in the US), this is a "tenth" (a pretty fundamental unit in machining is a thousandth of an inch, or a "thou", for very high precision work, that can be divided into "tenths", or ten thousandths of an inch).
- YZF 5y agoA mil, or a thou, really isn't good enough for high precision work. 25.4 microns is a lot. A surface flat to that isn't really that flat. An instrument that measures to that isn't really a very high precision instrument. Microns are a pretty good unit. EDIT: There's this rule of thumb (I might be getting this slightly wrong) that one in a million accuracy/precision is about what you can expect to achieve without resulting to exotic means (at least order of magnitude). So microns of flatness over a meter e.g. Trying that with imperial units just breaks my mind, what's a million mils. Sure I can calculate that. But it's like a pretty useless measure. So accuracy of one thou over a million mils is sort of weird. (1000 inches which I'd have to translate to some normal unit... 25.4 meters ;) ).
- JshWright 5y agoYeah, that's why tenths (~2.5 microns) are used when thousandths aren't precise enough. I'm definitely not claiming it's a good, I'm just describing the system I have seen used in the handful of machine shops I've spent time in.
- jbay808 5y agoI think YZF just mis-parsed your sentence, and thought you meant a thou is for very high precision work, while you meant that a tenth is for very high precision work. (That said, I'd add -- measuring to one part in 10^6, for anything except time, is challenging but still very doable; machining to one part in 10^6, for anything beyond very simple shapes, does require pretty exotic methods or very great care, and to verify it you have to measure to one part in 10^7).
- 5y ago
- lancebeet 5y agoI think "a tenth of the thickness of a human hair" would be an appropriate layman description of the approximate size.