xkcd

There's nothing in the SI system that says ratios have to be between base units. Units that involve mass are defined against the kilogram not the gram.

pfff at 2.7V that aint much of a danger, now show me 50F @ 2kV

Yes, I do not believe it. It must be a misprint, right?

That stucks ;-)

Wikipedia currently says:

the international avoirdupois pound, [...] is legally* defined as exactly 0.45359237 kilograms

So, technically, a pound is a metric weight, only a niche one whose use may or may not be permitted by local regulations.

Similar is true* of the inch, which is defined as precisely 25.4 millimetres.

* The US, UK and a handful of others collectively signed this into their respective laws in 1959. You might think we don't use the pound in the UK any more but it still shows up often in informal situations. Ditto inches and feet.

The joke wouldn't have worked as well.

A gram is actually a pretty small unit of weight, and the joke relies on the base units. It's actually a weird little abberation in the metric system that the "base" unit is considered the kilo gram. so a 1 gram rock would be a little pebble, strangely small.

It is my understanding that XKCD's "characters" are somewhere between an actual character and an archetype. It isn't clear...and kind of doesn't matter, if Black Hat is the same guy in every comic or if he's a different devious schemer in each. Randall hasn't bothered to name any of them so the community has given them unofficial nicknames.

I remember reading about their names in explainxkcd. I think the only one never named in the comics is Cueball.

For a while, there was a blog, but I don't think it named any character.

this guy gets it.

hogshead is my favourite

A rock that weighs one stone (14 lbs).

Or a barleycorn that's one barleycorn long? Or a really large foot that's a foot long. Or a chain that's a chain long?

A capacitor of 1 farad at standard American 120 volts has the energy between 7.62×54 and .50 BMG, and will discharge just as violently.