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by chrisseaton 3713 days ago
Or simply, one tonne. In fact I'd guess that the engineers, thinking in SI units, told the PR people that 'we recovered a tonne', rounding to that figure for them because it sounds neat. Then the PR people converted to pounds for older readers, which comes out as the very precise sounding 2,204. So the figure is probably rounded but then presented as being much more precise than it is.
4 comments

I don't understand this whole "tonne" thing. Why overload a word that already has two other conflicting meanings (the imperial short ton and the imperial long ton) when you already have a word that is more canonical and completely unambiguous in "Megagram"? Plus it just sounds cool.
It's only a problem in the US. The Commonwealth ton is only 1.6% larger than the tonne, so the distinction is usually insignificant. Most of the world has no knowledge of either the short or long ton.

Likewise, confusion between "mills" (millimetres) and "mils" (thousandths of an inch) are an exclusively American problem.

The American adherence to customary units is a constant annoyance for electronics engineers - an 0603 resistor could measure 0.6mm x 0.3mm or ~1.5mm x ~0.76mm

Sadly also a Canadian problem. We're nominally a metric country, but we're very much a hybrid. When we went to metric, many things still stayed in customary units, but with metric names. I'll likely never ask someone to go get me 454g of sugar from the grocery store, it'll be a pound. Your 2x4 is going to be 8 feet long. You're going to use 1/2" bolts. My generation does consistently use litres and celsius though!
I think the SMD resistors are well standardized.

A resistor measuring ~0.6mm x 0.3mm is an 0201. (2 1/100ths of an inch by 1 1/100th of an inch.) The standard doesn't make sense in SI units, but it's the standard.

SMD passives are listed in both metric and imperial units. Most sizes are unambiguous, but 0402 and 0603 resistors exist in both series. There's also possibility for confusion between the imperial 01005 and the metric 1005. These parts are specified in metric, making the imperial sizes purely nominal.

http://www.newark.com/chip-smd-resistors/resistor-case-style...

The metric/imperial split is a constant nuisance. Most board houses and PTH packages use mils, but the vast majority of SMT IC packages are specified in millimetres. Board layouts almost always necessitate switching between imperial and metric units; Layout software includes features to manage this. Wire gauges are a total mess - AWG, SWG and mm are all in common use. Standard pin headers and derivative connectors are 0.1" pitch (2.54mm), but JST connectors are 2.5mm pitch. Conversion errors have caused countless production problems.

Mils really confused me when I was learning PCB design. In the UK a thousandth of an inch is not a common unit anymore, but it isn't unknown. The problem is that we call it a "thou".
Because no one has any concept of that unit of measure. They use relatable units of measure, that's where the whole banana for scale thing came from because almost everyone has a grasp on the dimensions of a banana. People know cars weight tons and so a ton is a vastly more relatable unit of measure.
If you have a grasp on the dimensions of a banana, please make sure you've done so in the privacy of your own home.
There are few fruits that vary so much in size and shape as does the banana. Has anyone actually suggested using that as a standard for anything?
Some online communities use "banana for scale".

Other communities talk about radiation risk in terms of radiotion you get from a banana.

It's about as useful as double-decker buses or football fields.

The banana used for such measurements is your typical grocery store banana.
I hear well made bananas are also useful for terrorizing atheists. [1] Something about how they don't squirt in your face.

[1] https://www.youtube.com/watch?v=2z-OLG0KyR4

How much does it weigh in football fields?
Traditional measurement is not quite so simple. (All pounds avoirdupois.)

Short ton: 2000 lb.

Imperial (UK) long ton: 2,240 lb.

Longweight ton: 2400 lb.

I'm in the boat business where a register ton is 100 cubic feet.

There are more, especially once you get to other types of pounds.

So what is a tonne in British pounds?
one hundred pounds three schillings, two farthings and a sixpence
Unambiguous? As in megabyte?
Yes, it is unambiguous. No one uses binary prefix notation for mass.
No one uses "mega" for grams either.
Why not? It shows the relationship between itself and other metric units better than "tonne" does. It would start sounding natural if people started using it.
Because "mega" is ambiguous. It can mean different things.
Sounds right to me. If you look at Apple's report[1], all the numbers they list for material recovery are exactly divisible by 2204.

EDIT: Correction, all except for the number for recovered steel.

[1] http://images.apple.com/environment/pdf/Apple_Environmental_...

They probably picked the wrong archaic unit. Shouldn't it be measured in troy pounds?
But since this gold, did they actually measure the weight in international troy ounces, then convert (correctly or otherwise) to avoirdupois pounds, then maybe another incorrect or correct conversion to kilograms and metric tonnes?