Earth now weighs six ronnagrams: New metric prefixes voted in • Hacker News Board

Re: Earth now weighs six ronnagrams: New metric prefixes voted in

#171

Post by GuB-42 » Sat, Nov 19, 2022, 2:05 AM UTC

chrisshroba wrote: post #118

idiotsecant wrote: post #93

Earlier quoted context omitted.

It's not so strange - a lot of our natural experience of the universe is within 3 orders of magnitude of the base units we use. Those are very commonly referenced and as such have common prefixes.

Agreed, I can think of lots of use cases that come up in day to day life: - decade - century - decagon - centimeter - decimal system - decathlon - centipede edit: admittedly, hecto is pretty rare and centi is often used for both 1/100 and 100

The hectopascal is the most common unit for atmospheric pressure. It replaced the equivalent millibar to match SI units. Standard atmospheric pressure at sea level is 1013 hPa.

Hectolitres are commonly used in the food and drink industry. For example wineries and breweries typically measure their production in hectolitres.

Not exactly hecto but land, especially farm land is often measured in hectares. It is a non-SI metric unit equivalent to the square hectometer or 10000 square meters. We most likely kept the name because "hectare" sounds better than "square hectometer". As expected, 1 hectare is worth 100 ares, but ares and its other multiples are much less used than hectares.

Re: Earth now weighs six ronnagrams: New metric prefixes voted in

#172

Post by hypertele-Xii » Sat, Nov 19, 2022, 2:09 AM UTC

silisili wrote: post #151

allanrbo wrote: post #116

Earlier quoted context omitted.

That is almost like reinventing something like Roman numerals :-) Maybe better to stick with 1e48 notation after all.

It's kinda funny that you mention it. If we say to someone '99 hundred', they'd immediately understand it as 9,900. If we say 'hundred hundred', it's an immediate math problem trying to figure out how many zeros and what it's called. At least, that's how I'd react.

> If we say to someone '99 hundred', they'd immediately understand it as 9,900.

That's definitely untrue. In my native language we never mix tens and hundreds, and it always takes me a moment to parse that "thirteen hundred" means one thousand and three hundred.

Re: Earth now weighs six ronnagrams: New metric prefixes voted in

#173

Post by hypertele-Xii » Sat, Nov 19, 2022, 2:13 AM UTC

Aardwolf wrote: post #94

> "Jupiter, that's about two quettagrams," he added—a two followed by 30 zeros. But the sun is 2000 quettagrams... looks like we need another higher prefix

Exactly 1 Solar mass.

Re: Earth now weighs six ronnagrams: New metric prefixes voted in

#174

Post by geenew » Sat, Nov 19, 2022, 2:27 AM UTC

hypertele-Xii wrote: post #173

Aardwolf wrote: post #94

> "Jupiter, that's about two quettagrams," he added—a two followed by 30 zeros. But the sun is 2000 quettagrams... looks like we need another higher prefix

Exactly 1 Solar mass.

Need an epoch on that

Re: Earth now weighs six ronnagrams: New metric prefixes voted in

#175

Post by silisili » Sat, Nov 19, 2022, 2:47 AM UTC

hypertele-Xii wrote: post #172

silisili wrote: post #151

Earlier quoted context omitted.

It's kinda funny that you mention it. If we say to someone '99 hundred', they'd immediately understand it as 9,900. If we say 'hundred hundred', it's an immediate math problem trying to figure out how many zeros and what it's called. At least, that's how I'd react.

> If we say to someone '99 hundred', they'd immediately understand it as 9,900. That's definitely untrue. In my native language we never mix tens and hundreds, and it always takes me a moment to parse that "thirteen hundred" means one thousand and three hundred.

Ah, I should have specified in the US. It's more common to say numbers between 100 and 10k as hundreds, unless it's exactly on a thousand. I think most people would say nineteen hundred, or 21 hundred for 1900 and 2100, but nobody would say 20 hundred for 2000(except for military time).

Re: Earth now weighs six ronnagrams: New metric prefixes voted in

#176

Post by throwaway821909 » Sat, Nov 19, 2022, 2:50 AM UTC

idiotsecant wrote: post #135

chrisshroba wrote: post #118

Earlier quoted context omitted.

Agreed, I can think of lots of use cases that come up in day to day life: - decade - century - decagon - centimeter - decimal system - decathlon - centipede edit: admittedly, hecto is pretty rare and centi is often used for both 1/100 and 100

ah yes, the centipede. Famously the unit of measure of one hundred pedes.

well... yes?

> Centipedes (from New Latin centi-, "hundred", and Latin pes, pedis, "foot")

Re: Earth now weighs six ronnagrams: New metric prefixes voted in

#177

Post by MiddleEndian » Sat, Nov 19, 2022, 2:57 AM UTC

kevin_thibedeau wrote: post #133

kibwen wrote: post #92

Earlier quoted context omitted.

Specifically, this happened in 1893: https://en.m.wikipedia.org/wiki/Mendenhall_Order

The inch wasn't converted to a derived metric unit in the US until 1959. This creates an issue for precision machinery manufactured before the redefinition because the slight difference is enough to matter where allowed to accumulate.

If only some governing body had been aggressive enough to redefine NTSC 60Hz as actually 60 fps.

Re: Earth now weighs six ronnagrams: New metric prefixes voted in

#178

Post by arunc » Sat, Nov 19, 2022, 3:01 AM UTC

And here in US, we are stuck with imperial units like it was 1800s: oz, pounds, inches, feet, miles, etc for all common usage. When a foreigner visits here, the first thing they realize is how US has truly siloed itself from the rest of the world.

Re: Earth now weighs six ronnagrams: New metric prefixes voted in

#179

Post by saalweachter » Sat, Nov 19, 2022, 3:51 AM UTC

Someone wrote: post #52

opwieurposiu wrote: post #45

Earlier quoted context omitted.

Yes and the circumference of the earth is about 40 million meters. This is because a meter was originally supposed to be 1/10E6 the distance from the equator to the north pole through Paris.

Nitpick: 1/10⁷, not 1/10⁶. They picked the power of ten that gave a reasonably-sized unit of length. They also made things complex by then picking a unit of mass that’s inconsistent with that: a gram isn’t the mass of 1m³ of water, but of 1/10⁶ m³ of water (a cubic meter is 10³ liters, and a liter of water weighs 10³ grams) Centimeter-gram-second ( https://en.wikipedia.org/wiki/Centimetre–gram–second_system_... ) rea…

The gram is the easiest to save by working backwards from Avogadro's number.

Avogadro's number is close to 24!, so we could redefine our mass unit as exactly 24! hydrogen atoms (or 4!!) and that comes out to within about 3% of a gram while being significantly easier to communicate to an extraterrestrial civilization.

Re: Earth now weighs six ronnagrams: New metric prefixes voted in

#180

Post by rippercushions » Sat, Nov 19, 2022, 4:33 AM UTC

toast0 wrote: post #95

rockostrich wrote: post #86

Earlier quoted context omitted.

Is there a convention for prefixes for 10^n where abs(n) > 3 and n % 3 != 0? It seems strange to me that we would have prefixes for 10^+/-1 and 10^+/-2 but not for any larger values.

India commonly uses Lakh for 10^5 1,00,000 and Crore for 10^7 1,00,00,000. After that, there's Arab at 10^9, Kharab at 10^11, Neel at 10^13, and Padma 10^15, but as a US person, I've never seen those used, although I've seen Lakh and Crore. Sometimes lakh crore shows up, which is 10^12 or a (short) trillion, but sometimes trillion is used for that in documents otherwise using lakhs and crores and not billions or mill…

In Japan and China you use groups of 10,000, so there's 万 (1e4), the largest bill (10,000 yen); 億 (1e8, 100 million), the approximate population of Japan and a convenient unit for housing prices in yen; and 兆 (1e12, 1 trillion), which is used for eg really expensive infra projects like new bullet trains.

On paper, there are much larger units too, but they are never used.