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[Arcvasti]

...although I've had a couple of off-colour jokes deleted before, which is fair enough.

AAAAHH!! RACISM!

But to whom?

people who don't put a "u" in "colour"

[hector13]

...although I've had a couple of off-colour jokes deleted before, which is fair enough.

AAAAHH!! RACISM!

But to whom?

people who don't put a "u" in "colour"

Fackin' weirdos, they are.

[Ultimuh]

...although I've had a couple of off-colour jokes deleted before, which is fair enough.

AAAAHH!! RACISM!

But to whom?

people who don't put a "u" in "colour"

Fackin' weirdos, they are.

English is not my primary language, so wether or not I use the letter "u" depends entirely on whom I'm speaking to.
The problem is however when I don't know what country said person is from. 

[ChairmanPoo]

colour is perfectly correct.

[Orange Wizard]

Well, yeah, that's what we've been saying. It's color that's wrong.

[Execute/Dumbo.exe]

Well, yeah, that's what we've been saying. It's color that's wrong.

From what I can tell, though, this forum will only accept color when using colored text.

[Amuys]

I asked an Australian if Crocodile Dundee was an accurate representation of his ideal patriot. He responded by sending me a picture of Josef Fritzl instead.

[Orange Wizard]

From what I can tell, though, this forum will only accept colour when using coloured text.

Because the people who made the forum software were wrong. Duh.

[Sergarr]

why do people try to use the second law of thermodynamics so wrong

why do they always forget that it only applies to closed systems, and that our Solar System is not a closed system, because 99% of solar radiation goes away into space

i'm looking at you randall and your "hurr you can't gather the moonlight to ignite paper because i presuppose that moonlight is black body radiation (even though it's completely and utterly wrong) and 2nd law forbids objects from heating any other object to higher temperature than themselves, because, obviously, temperatures higher than 6000 K have never been achieved on earth, obviously" total bs

[Orange Wizard]

moonlight is black body radiation

hu

i think I lost a few brain cells just by reading that

[TheBiggerFish]

That doesn't even make sense.

[Lord Shonus]

Luckily, the article he's bitching about doesn't say that.

The Sun is about 5,000°C, so our rule says you can't focus sunlight with lenses and mirrors to get something any hotter than 5,000°C. The Moon's sunlit surface is a little over 100°C, so you can't focus moonlight to make something hotter than about 100°C. That's too cold to set most things on fire.

"But wait," you might say. "The Moon's light isn't like the Sun's! The Sun is a blackbody—its light output is related to its high temperature. The Moon shines with reflected sunlight, which has a "temperature" of thousands of degrees—that argument doesn't work!"

It turns out it does work, for reasons we'll get to later. But first, hang on—is that rule even correct for the Sun? Sure, the thermodynamics argument seems hard to argue with,[3] but to someone with a physics background who's used to thinking of energy flow, it may seem hard to swallow. Why can't you concentrate lots of sunlight onto a point to make it hot? Lenses can concentrate light down to a tiny point, right? Why can't you just concentrate more and more of the Sun's energy down onto the same point? With over 1026 watts available, you should be able to get a point as hot as you want, right?

Except lenses don't concentrate light down onto a point—not unless the light source is also a point. They concentrate light down onto an area—a tiny image of the Sun.[4] This difference turns out to be important. To see why, let's look at an example:

[Sergarr]

That doesn't even make sense.

behold

this is why mathematicians should not try to play physicists outside of theoretical physics and its direct applications

because then you get dumb shit like this:

Lenses and mirrors work for free; they don't take any energy to operate.[2] If you could use lenses and mirrors to make heat flow from the Sun to a spot on the ground that's hotter than the Sun, you'd be making heat flow from a colder place to a hotter place without expending energy. The second law of thermodynamics says you can't do that. If you could, you could make a perpetual motion machine.

Obviously, if you could concentrate heat from the sun to achieve temperatures higher than on the Sun, then you could make perpetual motion machine. This is why we, obviously, live in the current age of infinite energy, thanks to our laser-based perpetual motion machines, than generate temperatures higher than 6000 K. OBVIOUSLY

[TheBiggerFish]

That was exactly what I thought of when I saw that!  How did you know?

[Execute/Dumbo.exe]

That doesn't even make sense.

behold

this is why mathematicians should not try to play physicists outside of theoretical physics and its direct applications

because then you get dumb shit like this:

Lenses and mirrors work for free; they don't take any energy to operate.[2] If you could use lenses and mirrors to make heat flow from the Sun to a spot on the ground that's hotter than the Sun, you'd be making heat flow from a colder place to a hotter place without expending energy. The second law of thermodynamics says you can't do that. If you could, you could make a perpetual motion machine.

Obviously, if you could concentrate heat from the sun to achieve temperatures higher than on the Sun, then you could make perpetual motion machine. This is why we, obviously, live in the current age of infinite energy, thanks to our laser-based perpetual motion machines, than generate temperatures higher than 6000 K. OBVIOUSLY

Well... Yeah? I think? I'm unsure because of your wording but you seem to be implying that he's saying that sunlight does violate conservation of energy when he's saying the exact opposite.