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Exciting update! IDoNotCare had now been permanently banned for similar offences.

Really ? You guys are arguing about her use of the English language ? Aside from the fact that she is not a native English speaker, the word best is singular. There is only one 'best', and there is no differentiation between 'the best' and 'best'. In both cases it is the one that is better than all the rest. This 'tempest in a teapot' is not worth discussing, in comparison to the fact that she 'supports' her husband, which is worth discussing.

I am rather amazed that you have spent a decade researching this and you do not understand the difference between basic physics concepts. This is not a vernacular problem, this is a conceptual problem. You should go to a basic physics site and look up the definitions of velocity, acceleration, momentum, force and energy.

Did I read it right? You want to sleep 2 hours per day.. ? For how long? (that's silly to be honest) If you want to examine sleep, better get camera with IR, which will be pointing at you during sleeping, and recording your movements, and equipment measuring pulse of heart, and breathing, brain activity etc. etc. If you will be waking up in the wrong stage of sleep, you will be astonishingly tired.. People who known more about this stuff even made smartphone apps which are measuring at which stage user is, and starting alert prior hour and minute alert was set.. Because it is important to wake up in the right stage of sleep, rather than plain amount of minutes of sleep..

Worth mentioning that prevention is better than cure. Are you doing this in consultation with a doctor to monitor your health?

Both? I was sitting about 2 meters behind the flag, and zoomed in to the maximum. To be sure that the autofocus would not focus on the flag itself instead of the interference pattern, I focused manually, and exposed 2 stops (That is what they call it in Dutch) less than the lighting meter would normally do. And then on the computer I increased contrast, made it even a bit darker, and cropped to the pattern itself, so yes, it is pretty magnified. With my bare eyes I nearly could not see the colours. It was super, everything, everybody. I especially enjoyed the wine: very light, maybe only 6% alcohol, so I could drink much more than usual without getting tipsy or having a headache the next morning. Yes, that is definitely an advantage of living (and having salary) in Switzerland, nearly everything foreign including holidays, is cheap. Why, at the moment of writing, I realise I soon could buy the USA. I will think about a few improvements I could make then... ⚡

You're just missing a pair of square brackets.

C J Smith was Director of the Physics Laboratory at Kings College, University of London in the mid 20th century. He wrote several important texbooks for the sixth form and undergraduates. This was from the baby of them (mine is 1957) - only one thousand three hundred and thirty two pages -- Intermediate Physics. The undergraduate version runs to 5 volumes. Some of these older books have lots of useful subject matter in them that is no longer commonly taught.

I gave +1 because you have identified all the important features of the situation. The difference between heated and not heated The difference between the inerior and surface environments. I was offering a treatment along the lines provided by Prof Smith, along with some additional diagrams and explanations of my own.

I think you have a point that the OP's confusion comes from different defining conditions. I hadn't seen that. Evaporation would take place on the surface. Boiling would correspond to the situation when the water is heated (frequently it's from below). But evaporation, as generally understood, doesn't have to be an equilibrium situation: https://www.britannica.com/science/evaporation https://en.wikipedia.org/wiki/Evaporation The equilibrium situation (in my understanding) would correspond to equal amounts of molecules leaving the water than coming back. You need a closed container in general to get to that point. That's called evaporative equilibrium. But I suspect we call things differently. In order not to make the discussion more confusing, I would propose to try to sketch the two different scenarios that I think are mixed here and @studiot has suggested, by way of example: 1) A lake struck by a very hot Sun (mostly surface evaporation) 2) A cooking pot with water in it, taken to boiling point (bubbling more dominant and therefore more molecules escaping from within) And I would try to highlight the differences from there as clearly as possible, avoiding too fine points about equilibrium, stationary character, differences between kinetics and thermodynamics, etc. And would like to agree with @Daniel Waxman and share my part of the blame that we may have turned this discussion into something rather more obscure than need be. My experience tells me that insisting in what may only be terminological nuances can only bring more confusion.

I agree. +1. I have already stated that there are two separate situations described in the OP. They are thermodynamically and kinetically different. Evaporation is an equilibrium process. Heating to(wards) boiling is not. There is also the fact that liquid molecules at the surface have (on average) more energy than those in the interior, when the liquid is in equilibrium. I takes a specific amount of energy to bring a molecule to the surface. All this is most conveniently illustrated with simple diagrams.

If the water could be uniformly heated then we would see the same result of water vapor bubbling through the surface, but if you are excluding boiling from evaporation altogether then I would say it is impossible for evaporation to occur below the level of the water since by definition evaporation requires vaporization and that implies a decrease in density which would result in a bubble if it occurred beneath the surface. The dictionary.com definition of evaporate says "to change from a liquid or solid state into vapor; pass off in vapor", which does not include any qualification of what temperature at which this might occur. However that definition might be colloquial and not the one which is used in a scientific content.

Question: Do molecules below the surface of the liquid evaporate? Your answer: Water molecules below the water level can become gaseous. That explains the bubbling of water vapor through the surface of boiling water. I don't think that explains it, nor does it answer the OP question. Starting with: There is no such a thing as a "gaseous molecule". Bubbles are small domains of gaseous phase that form locally due to fluctuations (little variations of under-density, excess temperature, or both) which, by virtue of their lower density, and helped by convection, make it to the surface and are released, being much easier for them to break the surface tension than individual molecules. Any phase transition is governed by the formation of small subdomains of the final state. These subdomains appear and disappear constantly, but as the temperature approaches the boiling point or goes past it, they become more frequent, grow bigger, and last longer, thereby having more time to reach the surface and get released.

You need to provide that much energy to create the plasma. It is not a source of energy.

! Moderator Note First, without the maths, you don't have a model. Second, we won't be discussing religion-related ANYTHING in a scientific speculation. ! Moderator Note Third, science isn't interested in proof. Science works with theory, which is our best current explanation for various phenomena. Your whole approach is flawed because you think your "answer" is right and now you're trying to "prove" it no matter what, and that's NOT doing science. Belief is based on how trustworthy the explanation is, and the current model proves itself constantly, every day. You've had six pages to defend your idea, and you've gotten some EXCELLENT replies trying to help you form a more reasoned methodology. You've shown some improvement about taking new information on board, but you still ignore most posts that refute your idea. This would be a great time to re-read, re-calibrate, and reflect on the rigor with which you wish to approach your proposal. If you can find scientific ways to support it, and develop a mathematical model that allows you to make predictions based on your proposal, then PM a staff member and you can open a new speculative thread to discuss these new perspectives. Thread closed.

In mathematical terms, Omega is the same to-be-determined variable as in Example 2. In terms of Physics, it is the https://en.wikipedia.org/wiki/Angular_frequency. Example solution for Example 3: If I take x = x0 cos (wt) + v0/w sin (wt) and plug in x(t=0) = 0, then I get the condition x0 cos (0) + v0/w sin(0) = 0. Hence, x0 = 0. The first derivative of the function is dx/dt = w x0 (-sin(wt)) + v0 cos (wt). Plugging in the constraint dx/dt (x=0) = 1 yields w x0 (-sin(0)) + v0 cos (0) = 1. Hence, v0 = 1. The 2nd derivative of the function is d^2 x/dt^2 = -w^2 x0 cos(wt) - w v0 sin(wt). That one is a bit tricky, but by comparison you will see that this is -w^2 * (original function). So this satisfies the condition d^2 x/dt^2 = -x if w^2 = 1. I don't know why w=-1 is not considered here; maybe I missed something. Hope that helps. If so, it would be nice to hear what the actual step was that you got stuck on.

How are these a vibration of the molecule as a whole? Indeed so, did I not say say that the key motion is translation of the whole molecule ? How is this a vibration?

Better tell all these people, then. https://phys.org/news/2014-05-molecular-vibrations-hydrogen.html https://www.sciencedaily.com/releases/2014/05/140501142227.htm http://www.schoolphysics.co.uk/age16-19/Wave properties/Wave properties/text/Microwave_ovens/index.html https://www.azonano.com/news.aspx?newsID=36282 http://www.wiredchemist.com/chemistry/instructional/supplemental-material-for-chemistry/chapter-7/animations That last one also describes the most obvious form of vibration, which is also temperature dependent and so, presumably, what the OP was thinking of: Now, try saying that those are not "vibration" at the same time as saying that your definition is "not narrow".

Conduction will take place as well. But, in a liquid, heat transfer by convection will be much faster.

To give an even simpler answer: they get to the surface and then escape! That may be too simple to be useful. But as you add heat from the bottom, it will cause convection which brings those molecules up to the surface. Also, as the fastest molecules at the surface escape, the average kinetic energy of the top layer decreases; in other words it cools and so will sink lower in the container.

Something I posted in the 'what are you listening to right now' thread. Edit: Just to note, the above video isn't posted with humour in mind. It just something I thought was appropriate given the thread title, and the fact people were discussing it. Edit 2: really sorry if I've offended anyone with this. I found the film really moving, and I'll admit, fascinating too. I don't think the film is made with bad intentions.

Well, I would rather say it is based on what society deems harmful which overlaps only imperfectly with things being harmful. There are plenty of laws that are actually harmful, but were not recognized as such, for example.

Disclaimer : This is just a JOKE. If inbreeding was legal in the US, then all states would vote like southern states currently do, and we'd always have Presidents like D Trump. ( who incidentally, has made comments about how sexy his daughter is; creeeepy ! ) That alone should make it illegal as it is detrimental to society. This is serious. Laws are not based on whether they do harm or not. they are based on what society deems acceptable. You can get fined for spitting on a sidewalk, even if there is no one around, and every bar once had a 'spitoon'. You can get fined for smoking in a public place ( sidewalk café ) with traffic ( car exhausts ) going by 2m away. It is against the law to speed on highways which are safe at 20-40 km/hr over the posted limit. Need I go on ? Some things that were once common have become 'disgusting' to the majority of society; laws reflect that.

Given that any typical sexual relationship will fail with some degree of lasting animosity, the consequences of such actions in a familial situation would be catastrophic for the wider family. I think that is ample reason for it to be taboo.

What is the human form? Should I be able to remember my conception (the human form), would I be able to change form by thinking of that moment and, for example, deciding to become "an alien." Would have to wait for my conception to reach the moment I made that decision? : 0-------->1-------->2 ---------->0-------->1 Would a woman be able to become pregnant by thinking of her conception, and deciding that she was so???