swansont

Concepts don’t exist?

Then you can put it anywhere you like, but I think it needs to be rigid If it’s glass there’s no compression. The glass provides the force on the water. But you can observe what 20m of water would do to visibility, since we have situations like this. Things would be very blue https://www.researchgate.net/figure/Penetration-of-Light-of-Various-Wavelengths-through-Water-Blue-Light-is-the-Strongest_fig3_220785640 http://oceanography-leahmoore.blogspot.com/2010/10/light-attenuation-for-various-colors-of.html

That amount of water, as vapor, is my take. I'm going to answer a slightly different question, to start (there are so many ways the scenario is just impossible). Let's assume we have 1 square cm of surface. 10 meters of water is 1000 cm, so we have 1000 cm^3, or 1 liter (mass of 1 kg). We're going to vaporize this by raising the temperature and then boiling it. To heat it up to boiling requires 4184 J/kg per ºC. If we start at 20ºC, that's 3.35 x 10^5 J. That's the easy part. To vaporize this water requires 2260 kJ of energy (2260 kJ/kg) (i.e. 2.26 MJ) Result: ~2.6 MJ. For every square centimeter of surface. And double that, because you wanted ~20m. More than 5 MJ/cm^2 That energy must be released when you go back to a liquid. This has an effect on temperature, to be sure. 2 bars of water is going to make for pretty difficult breathing. You've now tripled atmospheric pressure, assuming you can get this much vapor in the air (I don't think you can) and what you're breathing is mostly water vapor. Oxygen has dropped from ~20% to less than 7%

! Moderator Note Yes. Posting this evidence is required for further discussion. Otherwise, the response is “good for you” and thread closure, because we’re a science discussion site.

less divergence.

Blessed are the cheesemakers (really, any makers of dairy products)

All of these can probably be looked at with an historical lens. Humans from 5k years ago and isolated from other populations show, at most, minor physical differences. They were around different animal species, and so different diseases, so they would likely be susceptible to each others’ diseases. Just like “old world” and “new world” populations. Language would also have diverged.

Thank you. Never noticed that (each time we update the software, I am less interested in poking around to explore all the features). Looks like blocking followers is all or nothing.

All lasers eventually diverge; most can be described by gaussian profiles, so they have a minimum spot size (“waist”) at some distance from the laser. Making the beam fat actually improves the divergence issues. The laser used for the moon ranging measurement diverged to be ~2 km across by the time it got to the moon (the atmosphere’s changing density played a part in this); the beam started out several meters wide https://tmurphy.physics.ucsd.edu/apollo/basics.html We use the telescope as a gigantic (3.5 meter wide) laser pointer and also as a signal receiver. Staying close to 10 cm over 1 km would seem to be possible with good optics+optomechanics and the right laser (for example, laser diodes, such as ones found in laser pointers, have horrible inherent divergence issues)

I’m not sure how to find the list of people following me.

Laser implies a certain source (stimulated emission). There may be issues of coherence of the light and beam quality with beams, but I’ve used 50mm beams without any issues. Still able to do laser cooling and trapping. We expanded the beams using lenses. I can’t see your embedded image Vision impairment is an intensity issue, which is made worse by having a collimated beam The eye is most sensitive in the green (555 nm), ~5x more sensitive in green than red (~650 nm). this shifts a little toward shorter wavelengths if your eye is dark-adjusted https://www.ncbi.nlm.nih.gov/books/NBK11513/figure/ch24psych1.F10/ The effective range is going to depend on the beam’s divergence. If it’s 10 cm at the target, a few mW should be visible.

JohnSSM has been suspended to see if he can get rid of the chip on his shoulder. Stirring the pot because you’re bored isn’t an acceptable exercise

! Moderator Note I already addressed this: you referred to it as “my theory” and admitted it was only supported by a few people. This isn’t a negotiation of whether you must follow the rules. Since you only seem to be here to stir the pot, I guess there’s nothing more to discuss.

It’s not a speculation. The OP asks a question, rather than asserting a position. No reason to move it, unlike your hijack to whine about the mods.

! Moderator Note Irrelevant. I’m not engaging on points of fact or knowledge. I’m pointing out the rules. Given your length of tenure here, you should be familiar with them ! Moderator Note It can’t be common knowledge if you need to study it in advanced courses at a university. But if it is taught as such, supporting it should be a trivial task, and you shouldn’t claim ownership of the theory. ! Moderator Note Of course they can be argued, and your position seems to mean they are easily supported, and challenges rebutted. So support/rebut them.

! Moderator Note This is an unacceptable position to take. We expect arguments to be made in good faith, and declaring you will not answer questions does not comply

! Moderator Note Not in the areas of science with which I am familiar. Mainstream topics are taught in universities and many people write textbooks explaining the subject. They publish in respected journals. It’s generally not hard finding supporting literature. Non-mainstream ideas are the ones that are brought up in discussion boards, because there’s little traction for them. Sometimes there are multiple proponents of the idea, but sometimes not. This sounds like the latter, thus it belongs in speculations, per the rules of SFN.

! Moderator Note You refer to it as “my theory” so I have to wonder which claim is misrepresentation. Is it your theory, or not? If it’s not, you shouldn’t say it is, and it should be easy to support your claims with citations.

! Moderator Note Since we can’t seem to follow the rules, we’re done here Don’t bring this topic up again

! Moderator Note Was there something you wanted to discuss? Just advertising a link is not permitted; it has been removed.

! Moderator Note A couple of things: When you present a theory of your own, you own the burden of proof. It is incumbent upon you, not others, to ensure it is complete and well-supported. It not inherently rude to be asked to clarify or support a claim. "I don't own/haven't read that cite" is not a rebuttal of a claim ! Moderator Note As far as I can see (within limits of the search function of the site), a member pointed out you were being snide ("taking a snide swipe") while discussing the clarity (or lack thereof) in your writing. I don't see where you were warned never to be snide, even without the caveat that the only real "warnings" come from staff members, whether they are modnotes or official ones issued through the forum software. While revisionist history is potentially a problem, it is also the case that an attitude that "my writing is clear and I will brook no disagreement to this" is not an attitude that will be accepted. It's not consistent with cvonversing in good faith. A member commenting on your style is merely suggestion that you may want to polish things up a bit, just as you have made similar comments to others. Any suggestion that others must conform to your standard but you are under no obligation to conform to theirs is probably not going to serve you well, but is not, in most cases, a rules violation in and of itself. (Though it is potentially a gateway to such) Please return to the discussion of the topic at hand

I'd have to think about this. The acceleration is there, but we are also in freefal. about the sun owing to our orbit. (Need caffeine to make brain work) edit: A confounding factor is the change in the mass distribution of the earth owing to the tides. g gets bigger or smaller because of the moon or sun, but the water moves around if you're near the coast, and all that water moving depresses the crust a small amount. The net effect is the body being overhead reduces g, but the nearby mass increases it, reducing the net effect As it's a tidal effect, the impact of the sun is smaller. As you would be getting closer to the limit of the pendulum clock's stability, the difficulty in measurement is bigger than the simple difference in the magnitude of the effect; the net variation is (IIRC) a few milliseconds per day, and the limit of the best pendulum clocks are a little under a millisecond, so the sun's effect is closer to being lost in the noise (S/N of 5 is markedly easier to measure than a S/N of less than 2)

The lesson here is that all of physics is approximation. There's always more to it when you dive deeper into any topic.

I think you'll find having proficiency in math will help a lot with being able to work chemistry problems. Good luck!

! Moderator Note 1. without reading the link, I can say that they do not give good evidence 2. You must present evidence here, not just give links (see rule 2.7) 3. Advertising your other threads is also against the rules