wayne_m

When I said CO2 would become poisonous, I meant that in high concentrations, we can't exchange enough out of our bodies, and blood becomes more and more acidic. This is the reason that we feel an urgent need to take a breath, after holding it for an extended period of time. Even if there is plenty of oxygen in the air, if there is too much CO2, you still die. The poison is the dose.

A linear rise in gas concentration does not equate to a linear rise in absorption of radiation. There is only so much energy to be absorbed. Typically, as gas concentration rises, absorption increases by logarithmic reciprocal. This kind of conversation is usually about CO2, so I'll just say that the change in absorption between 400 ppm and 800 ppm is vastly less than the change between 200 ppm and 400 ppm. In fact, the greatest rise (by orders of magnitude) happens well before 100 ppm. CO2 will become a threat as a poison before it becomes a serious threat due to heat. Add to that that the atmosphere is a stew of many different gases, all with different chemistry and physical characteristics, and you can know one thing: anyone who claims to understand it completely is lying to you. Anyone who claims that his model is definitive is trying to sell you something.

"A little song, a little dance, a little seltzer down your pants" It took a while, but my memory was finally jogged! Chuckles the clown. One of the funniest episodes from the Mary Tyler Moore show was when he died. How did I not remember this?

I've pondered this while driving long distances. I'm odd, that way. There really is no reason that it should be impossible. Insanely expensive, sure. But not impossible. Lower some strands from your geosynchronous station, and support a secondary platform, while extending a counterweight. Then from the lower station, lower a smaller number of strands to a smaller platform, and so on, until it reaches the ground. Once you have a functional elevator, use it to haul more building materials to the station, and begin making it stronger. There is no real reason a cable has to extend the entire distance. This could work with just about any material, but obviously, the station and its cables would have to be a great deal larger (and thus heavier) to support the weight as the elevator gets longer. The reasons we haven't done something like this are 1) it would be hideously expensive, and 2) the cables would oscillate, and without some way of damping that oscillation, it would eventually tear itself apart and/or yank the station out of orbit. If such a thing could be started, then it might even be a good idea to transport the building materials up through a pipe, as a liquid, and make the cables on the station. All sorts of materials could be carried up suspended in a liquid medium - we could even use magnetic medium in the liquid and an electromagnetic driver to act as a "pump" to move the fluid. The magnetic particles would be pulled along much like the mag-lev trains already in use. They would drag the fluid - water, perhaps - along with them. Letting it fall down another pipe after the payload is separated would provide some return energy. Then you'd only be spending energy to overcome the effect of gravity on the payload and the fluid resistance from the pipeline - unless you could separate the liquid from the walls of the pipe, in which case, it would flow much faster, as an added bonus. Using a flow of gas instead of a liquid could work, too. You could even put stations on the platforms that would reduce the lifting medium at each step, as gravity becomes less of a hindrance. Then the concentration of the payload would increase each time. Or maybe an osmotic pipe could let it happen gradually, with better efficiency.

That's something I have a hard time understanding. If the reflected photon carries away the energy it brought into the collision, where does the equation get the energy that goes into changing the momentum of the sail? Do all of the photons reflect, or do some get absorbed? Do the ones reflected just lose energy to a drop in frequency?

If you look at the base of the bulb, you will see the hoax. It can unscrew from the plastic globe to insert a battery.

There's heat capacity and there's heat conductivity. A high capacity material can feel warmer to the touch if its conductivity is low, because even though it will absorb more heat, it will do it more gradually than a lower capacity material that can transfer the heat away from the point of contact more efficiently. That is why a chunk of cold lead lead wrapped in a towel will feel warmer than a glass of water of the same temperature. The lead will eventually absorb more energy, but the glass will carry the heat away from your hand relatively rapidly. The same thing happens with a wooden tabletop or chair vs a steel surface. The wood, being more massive, will hold more heat than the thin metal, yet it feels warmer - initially, at least. After prolonged contact, the steel will have absorbed all the heat it can, and after the same time in contact, it will feel warmer than the wood, which is still absorbing and diffusing heat through its mass. Of course, the steel will be cooling from the other side, so once the wood has had time to absorb enough heat, it will feel warmer than the steel again, since it is a better insulator against the heat loss to the air.

What about the water vapor in the air in the top half?

A theoretical guitar string may have a perfect sine wave as it vibrates, but that vibration causes resonant vibration within the instrument, which complicates the waveform. Every piece of the instrument will have some small effect on the form of the sound wave emitted, and there is no way that any two wooden instruments could produce exactly the same changes in the sound. They can be extremely close - maybe even enough that a human ear couldn't detect the difference - but they will be different.

WBAGNFARB = Would be a good name for a rock band. We got a lot of use out of this on another forum I used to frequent. Example, someone mentions "Occam's razor." Occam's razor WBAGNFARB. This could be used for so many terms of physics and astronomy...

Ow, ow, ow... I'm not even good at Latin, but it still hurts. Dictare - to speak, videre - to see "Altum sonueram," maybe? Or "...scriptus sit...?" [edit again] Okay, now that I've had time to google around a bit... ...How have I never seen these lists of useful Latin phrases?

Out of curiosity, where did you get the tagline? It's a bit confusing; the cases don't seem to match. Minimus is nominative singular, but cantorum is genetive plural. Balorum isn't even really a word. "Carborata" might be a play on carborundum, so sand? It's not Latin. "Panto" means "everything." I'm guessing, by context, that whoever wrote it meant "trousers." Unless it means that a little carborata makes everything fall down. Maybe it should be: "Candantus minimus, Ballandus minimus, Bracca mea arenam minimam labendo" (A little singing, a little dancing, a little sand [going] down my trousers)

If they are lighter than water, float them. One will float higher or lower than the others. If they are heavier, drop them in and see which one takes more or less time to hit the bottom than the rest.

Is it really half empty, though? https://what-if.xkcd.com/6/

An architect, an electrician, and a civil engineer were discussing religion. The architect said, "God must have been an architect. Look at the human body! Such elegance of design! A structure that is strong and light, and allows mobility, coupled with an efficient and effective motive system..." He's interrupted by the electrician: "God must have been an electrician. Look at the wiring system. Self-powered, and such intricate connections throughout the whole body..." They both notice the civil engineer shaking his head. He says,, "God must have been a civil engineer. Who else would run a toxic waste pipeline through a recreational area?" And for our Jewish friends: Two Jewish mothers were sitting in a restaurant. The waiter came to their table and asked, "Is anything all right?" An MIT student takes his girlfriend to a local bar. He tells the bartender, a classmate, "I'll have an H2O." The girlfriend says, "I'll have an H2O, too." So many punchlines for this one. He didn't care for her reaction, when she drank it. The date went well, until she blew up at him. Turned out to be a pretty hot date. The bartender gave her water, because he's not a complete idiot.