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>> Well, with no actual data to estimate with, it's kinda hard. :-P
>
> The point is you are meant to have a rough understanding of density of
> gases.
>
>> Heh. Well, I have no idea what the volume of this room is.
>
> Usually best to simplify it to a shape that it is easy to calculate the
> volume of, ie a cuboid.
This room *is* a cuboid! ;-)
>> I don't even "really" know how big a meter is. It used to be the
>> length of my arms, but they're a tad bigger now. ;-)
>
> You can estimate though, I suspect you can tell if your room is 2 metres
> long or 10 metres long, or 50 metres long. Remember you are about 2
> metres tall...
If I had to guess, I'd say this room is 3 m by 3 m by 3 m.
>> (E.g., off the top of my head Oxygen is supposed to be something silly
>> like 0.000004 g per cubic meter or something.)
>
> Wikipedia tells me it's 1.429 kg per cubic metre...
Really? Wow, that's pretty crazy... I'm *sure* when I looked it up it
was way less than that.
Ah, here we go: H2 is "0.08988 g/L". Apparently air itself is heavier
than that.
(You would, of course, *expect* air to be heavier than the lightest gas
in the universe. But not thousands of times heavier...)
>> Now, see, I was under the impression that lagging traps air, and hence
>> the "effective" surface area would still be the same.
>
> No, because the lagging has thickness, and the outer surface of the
> lagging is the effective surface area for radiating the heat. Even
> though the surface temperature will be less with the lagging, for small
> radii the surface area increase is enough to overcome the effectiveness
> of the lagging. Obviously the exact radius depends on the situation,
> but there will always be a minimum value where lagging works (below that
> it has the opposite effect than you probably imagined).
Heh. So does it matter which bird then? A hummingbird has different size
legs to an ostrich. ;-)
>> Aww, c'mon! I thought that was a really neat drawing! :-D
>
> Yes I have to admit it was pretty cool.
WIN! :-D
>> ...OK, I am now completely bemused. Apparently e^3 is roughly 20. I
>> cannot work out how that can possibly be. 2^3 is clearly 8. My head
>> hurts just thinking about it.
>
> Think about 2^3 and 3^3, then e^3 doesn't seem so bad.
If I could actually compute 3^3 mentally I'd probably agree with you. ;-)
>> As an aside, I notice the difference turns out to be especially tiny. :-P
>
> Would have been cool if e^pi = pi^e
I can't find it now, but I'm pretty damned certain there's a quote on
Bash.org where somebody claimed this was true, and some poor sap spent
hours trying to figure out why their math implementation was wrong...
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