Hacker News Reader

Comment by bigDinosaur | Hacker News Reader

4k kg is a little bit hard to parse, I missed the k after the 4 on first glance. 4000kg -> 130kg in case anyone else does the same mistake.

View on HN

I've edited the headline to change 4k (done by HN when submitting the story) back to 4000.

If only there was some other way they could use to express a change of 3 orders of magnitude for an SI unit.

The problem there is that the most obvious solution (4 tonnes) is a non-SI unit (but admittedly widely accepted), while the true SI solution (4 Mg) is even more confusing.

Just compare to animals. They went from an about an elephant weight of waste to about half a donkey weight of waste. That has the benefit of giving people something to help them visualize the difference.

Why do you want me to visualize half a donkey?

I propose Great Dane dog as an alternative.

It's confusing hearing that a lab went to a Great Dane.

Donkeys can weigh up to ~590kg so that's not very useful. I guess you were thinking about miniature donkeys.

Is 4Mg that confusing?

Yes, nobody does that. The SI base unit of mass is the kilogram, not the gram. (Yes, it's weird that that's the case. No, it's still not a good idea to buck the trend.)

...which brings us back to 4 kkg -- 4 kilokilograms!

Honestly we should just introduce a new name for the kilogram and make the gram a millifoo.

Millifoo has a mellifluous sound to it.

In the original version of the metric system, the base unit of mass was the grave, corresponding to the kilogram. 1/1000 of a grave was a gravet.

And from what I heard, grave sounded to much like 'duke' (in French or German), so the French Revolutionaries weren't too keen on it.

The French word for 'duke' would be 'duc' (pronounced more or less identically to the English word, for the obvious reason that the English word is borrowed from French). The German word appears to be Herzog. It's hard to see where either word might be plausibly confused with any possible pronunciation of "grave".

https://fr.wikipedia.org/wiki/Grave_(titre) somewhat equivalent of count or earl

https://en.m.wikipedia.org/wiki/Graf

You are right that it wasn't the equivalent of duke. I was being a bit imprecise. Sorry.

The better English equivalent to German Graf would have been an earl.

Double prefixes were actually common for some of the more "extreme" magnitudes a long time ago, like this one for example:

https://en.wiktionary.org/wiki/micromicrofarad

If I see "4Mg" in print, it's more likely that someone erroneously capitalized the 'm' in "4 milligrams", rather than sincerely using "megagram" as a unit.

It's just not done. Maybe that's weird, or inconsistent, or whatever. But it is that way.

There is the option of just writing it out “4 megagrams”

I guess, but that's longer than “4,000kg” and unusual to boot. Anyone reading it is going to convert it in their head to 4,000kg anyway. Four million grams is not something relatable. Hard to picture the weight of millions slips of paper vs. a few thousand large water bottles. Or roughly two sedans.

The megagram is on the same list as the dekaliter and the hectowatt. They don't exist :)

During my undergrad we had a physics professor who would only use si units. 3,000 km became 3 megameters. A billion dollars were a gigadollar. To this day I don't know how I feel about it.

The sound of "gigadollar" really tickles my fancy. Is a penny one centidollar or ten millidollars?

A cent is already a centi dollar.

4 * 10^3 kg

4e3 kg to 1.3e1 kg

Reply on news.ycombinator.com