darklight03/StackMIAsub huggingface dataset:
Does water vapor generate electromagnetic radiation/photons when it condenses into water droplets? I know that gas water molecules need a condensation particle to combine into water droplets. A pair of molecules combine on the surface and in the process transfer their binding energy into the kinetic energy of the condensation particle. Are any photons emitted during this transition? I'm guessing that the answer is no. By analogy, in the gas state a water molecule can be excited into a an unstable radiative state by colliding with an air molecule like nitrogen. Similarly it can be de-exited without radiation by a collision as well.
The twin paradox is resolved as the twin who moves through at least two inertial frames has a shorter worldline (therefore less time elapsed in their frame) than the twin who remains in one. I know the crucial aspect is the multiple frames not the acceleration, since you can have variations of the twin paradox with no acceleration. Besides calculating the proper time for each twin's path, is there a (perhaps more intuitive) reason that changing inertial frames will lower the time elapsed on your watch?
If an isosceles triangle is inscribed in a circle, then is it's altitude always greater than the radius? If yes, then why? My sir said that if an isosceles triangle is inscribed in a circle then its altitude is always greater than the radius and passes through the centre of circle but I don't understand why it is so and is it not possible if any other triangle is possible that is isosceles and has its altitude less than the radius of circle in which it's inscribed.
The question was to transform this sentence from positive to comparative degree: She is not so young as I expected. Following the solutions of other sentences of this kind (the photo shows a similar kind of problem from where I adopted the solution) it can be written that: She is not younger than my expectation. I want to know why ...I expected has been changed to ...my expectation. What is the grammatical rule here? I don't get it what's wrong with ...I expected ? Is it wrong not to use possessive pronoun? The sentence transformation is from the past exam question of my student which she couldn't solve. I am her private tutor and want to teach her the correct things. Please don't misunderstand it as a homework.
In the current approach of QFT, we model the process of creation of a particle (say a photon or a gluon out of a quark) as "instantaneous", meaning happening at a moment in time without any neighborhood (modeled via a delta function). To what extent is this an idealization of the real behavior of nature? Do we have any experimental evidence that this process happens with a certain duration? Can nature behave in a way which is more similar to a 'spike' rather than a smearing function? If this process have a certain duration - what properties does a particle has during the time it is 'in the making'?
My teacher gave us the assignment to find the moment of inertia of any shape you want. So I decided to find the moment of inertia of our milky way galaxy. I found out that our galaxy is shaped like a warped disk, not a flat. After I knew about that, I looked for the equation of the Milky Way's shape. But, to me, Nasa's and some high university papers had so many big wards that I could bearly understand what they were talking about(I'm Korean.. ^^). I'm sure that I can understand the equation if I had it, but I just can't find any information about them. I would really appreciate it if someone could tell me what you know about these equations (shape). Thank you!
I've a box with know width (W) and height (H) It has been rotated around an origin point O at a known angle The rotated box is enclosed in a bounding box for which the top-left point (Bx, By) and dimensions (Bw, Bh) are known Given the origin point, the angle, and the resulting bounding box, is it possible to determine the X coordinate of the original box (Ux)? I tried illustrating this in the following diagram.
Hi :) What properties of triangles should I use to solve this problem? I can work out the size of the large triangle and all of its angles, but how do I apply this to the circle? What am I missing? This problem is from the first chapter of a trig book, so the methods needed can't be that advanced. Just need some pointers. Thanks! https://i.stack.imgur.com/BEXKX.jpg
I created my lecture notes using the CambridgeUS theme. My students cannot get the .pdf file to print from Adobe. I tried printing my notes from Adobe on two different printers and I get the following message: "The document could not be printed, kindly use our help page to troubleshoot." Adobe's help page didn't solve my problem. Other pdf files print fine to these same printers, and I have had no issues so it isn't the printers. I have tried every theme in beamer and have no trouble printing the same notes if I use Boatilla or the default theme. Thankfully, I have a work around. However, I am still wondering what I am getting wrong or missing when I use CambridgeUS theme. And advice, insight? TIA.
is there a computable algorithm which lists all the finite subsets of natural numbers ?... i know that such a set is atleast countable... but can't determine if we can list every such subset in a computable manner ..... the set of all infinite sequences of the subsets of natural numbers is obviously uncomputable i think this problem should be computable, since any finite set is computable... but i need some sort of proof or reference , any site etc... thanks
Is the measure of a simple closed curve consisting of two arcs transversal to a foliation equal to the sum of the measures of these arcs? Let A be an arc that is the union of arcs B and C, where arc B is transversal to the foliation and arc C is contained in a leaf of the foliation. Is the measure of arc A equal to the measure of arc B? Is the measure of open arc equal to its closure? Thanks.
what I have been told is that present participles are used in active reduced relative clauses. considering present participle of "be", which is being, I was wondering can we use the same pattern? Another example in Longman dictionary is: who heard of a grown man being scared of the dark? or who heard of a grown man who is scared of the dark? Aren't they possibly equivalent of each other? Thanks in advance
In Kittel's book of Solid State Physics, it is said that, whenever an electron passes the positive ion core in the lattice, it has the ability to distort the lattice s.t by attracting the positive ion cores. Does the attraction has to do anything to the mass of an electron, as being small, does it posses the attractive power to make the nearby positive ion cores to pull toward that electron, as positive ion cores are much heavier.
I am reducing a block diagram manually and am not sure whether the following step is a valid step? I am using the rule of moving a summing ahead of a block in reverse. Reduction Step in Question I've checked the resulting transfer function before and after this step using MATLAB (connect function and Linear Analysis in Simulink) and they aren't the same, leading me to believe this isn't a valid step. Any help is greatly appreciated.
In a uniaxial crystal there is an optic axis, an extraordinary axis, and an ordinary axis. The optic axis is not the direction in which we plan to propagate light. The light is propagating in a direction such that the electric field might oscillate parallel to the optic axis. I have included a hand-drawn diagram below. What about the crystal determines how the optic axis is oriented? Is one of the principal axes (ordinary / extraordinary) always parallel to the optic axis? How is the ordinary axis distinguished from the extraordinary? What happens if I propagate light along the optic axis? In a uniaxial crystal, is there a third refractive index that comes into play?
Consider approximating a binomial distribution with normal. Originally, my binomial distribution is discrete, where the heights of the bars represent the probability. However, after approximating this distribution with a normal one, we find the probabilities using the area beneath the normal curve. How have the probabilities just changed from being heights to area? It seems unintuitive how these probabilities are more or less the same.
I accidently deleted a large part of my work on a .tex file. Unknowingly, i saved the file , ran the typeset once and closed it. Hence the content is deleted from the pdf too. Is there any way to retrieve the deleted content. I check the previous version of the file too but it is not available either. Somebody please help. I am desperate.
As we know that Euclidean geometry deals with triangles, quadrilateral,... and circles. Later in college we learn projective geometry but in quite modern language (vector spaces, equivalent relations). My question is, is there any roadmap or any book to learn projective geometry from high school Euclidean geometry which would be easier for high school student to learn projective geometry. I think it would be really helpful if our student could have some intuition with projective geometry before learning sth more modern like algebraic geometry.
Work done in an isentropic process does not cause dissipation but leads to change in temperature of a system. But temperature allows wider range kinetic energy to be accessible leading to more microstates. This should lead to increase in entropy, but this doesn't seem to happen here. Does this mean that increase in entropy is compensated by something else? Or am I making some mistake here.
I have a rotated retangle and a rectangle. Both are defined by their corners (however, for the non-rotated ones I also have access to topLeft, topRight, etc). Is there a way I can check if they intersect? (It would be enough to know if they intersect, even without knowing the extent of their intersection). I found solutions for two non-rotated rectangles and two rotated rectangles . Technically the solutions for two rotated rectangles could work in this case but I think that, since i know one of them is axis-aligned, there might be a faster way..
I recently read that neutrinos have a polarization property---their polarization is opposite to antineutrinos. Is it possible to determine the polarization of a neutrino? For example, we can determine the polarization of a photon using a polarizing beamsplitter, V-polarizations will be reflected into detector A, and H-polarized photons will pass through into detector B. Can we do something similar with neutrinos, something like a neutrino beamsplitter? (Of course, neutrino detectors are huge, but in theory?)
Using the GeoGebra program a few days ago, I came up with a wonderful feature about the parabola and the circle kissing its peak. I don't know if it is new or previously discovered. Please, if it was discovered previously, put a reference mentioning it in the comments, and in any case, can anyone prove it I don't think a lot of words are needed, this picture includes intuition
I was reading Ali Omar text on solid state course and it said about the fact that electrons in a lattice or in a periodic lattice never scatters or make collisions with the positive ion cores, as the eigen functions of the solution of Bloch's theorem have infinite lifetime and eigen functions do not gets scattered? I do not understand as why eigen functions never scatters and what does scattering of eigen functions means and also what does it mean by saying eigen functions has infinite life time?
I am trying to format a line of text that has two different sized fonts such that the vertical alignment of the smaller sized text is based off the larger sized text. In one instance I'd like the smaller text to be vertically centered on the larger text, and in another I'd like the smaller text topline to be aligned with the larger text topline. To my admittedly very limited understanding, this should translate to to changing a paragraph parameter to change the paragraphs vertical alignment to either "center" or "topline".
Data rates are higher in X-band, but considering free space path loss and atmospheric attenuation(diffraction I'm assuming is significant here), won't lower frequencies stand a better chance? Again, cost and weight is a factor, but I want to understand the physics that goes behind these selections. Additionally, why do uplink and downlink frequencies differ in which one is higher?(Uplink is higher in the case of C and X band whereas it's lower in S band)
Hello fellow grammar lovers! I need some help. I'm working on HR resources and have run into a bit of a conundrum about how to write about PTO. I know that I "would like to take time off." But how do I go about "initializing a time-off request?" My question: Is it appropriate to hyphenate time off when used as an adjectival noun to modify request? My first thought is to use the hyphenated version to describe the noun (request), as nouns used to modify other nouns become adjectival nouns/noun modifiers/attributive nouns. Thoughts? Thanks! J
Both mass and entropy behave differently for black holes than for normal matter. For simple Schwarzschild black holes, mass is proportional to their radius. The Bekenstein-Hawing entropy is proportional to their surface. Of course, the calculations for the two results can be found in the textbooks. Is there a simple explanation for why the dependencies on the radius differ? For example, fourfold surface implies fourfold entropy - but only twice the mass. In contrast, in normal matter, fourfold entropy implies fourfold mass. What is the best way to explain that in black holes, entropy increases more than mass? Somehow, mass and entropy are decoupled. What is the best way to explain this?
I understand that according to Collins Dictionary, a suffix is an affix that follows the stem to which it is attached, as for example -s and -ness in dogs and softness. It has, however, a second definition: anything that is added at the end of something else. Would I then be right if I say that the following sentences have the same suffix " is a vehicle."? An airplane is a vehicle. A car is a vehicle.
When a magnet is moved into solenoid, it induces a current. And, when it is moved out of the solenoid, it induces a current. But what about in the example below. When a very long magnet, that has its whole body within the solenoid, is moved in some direction. The magnetic flux experienced by the coil from the magnet, should be very similar even if the magnet as a whole was moved a few centimeter.
I searched for it but couldn't find any answer for this. For a light source is it simply the average of the full spectrum power? And how do you compute it for an image? How can you tell the difference between a yellow object lighted by a brighter light and a white object lighted by a yellowish light? Or maybe you can accurately compute it in front of a white sheet? Edit: I am talking about a lighting Kelvin temperature (for example of a bulb) rather than the actual temperature of the light source.
Approximating the Earth by a circle with West facing in the theta-hat direction and East in the opposite, when a person jumps up, the Coriolis force faces West according to the right-hand rule. Upon descent, the Coriolis force faces East. Since you spend an equal amount of time rising and falling, shouldn't the effects of the Coriolis force cancel out? Why is this not the case? Why does a person end up falling slightly West?
I'm helping edit a piece of fiction, which has a sentence that begins so: In another smaller kitchen... How is this to be punctuated? One choice is to leave it as it is. Another is using two commas: "In another, smaller, kitchen..." Since 'another' isn't an adjective or adverb, the usual rule(s) about grouped modifiers don't apply. (Note that there is a different kitchen several paragraphs before the line in question.) So--commas, no commas? (I can't see 'one comma' being right)
So in flrw metric it's quite reasonable to take eigenvalue of the time-like component of the stress energy tensor and identify it with mass density. Now, if someone argues the cosmological constant comes from the stress energy tensor. Wouldn't they also have to account for the change in mass density? In the Newtonian limit I'm pretty sure this is a change in mass density. How do people who argue it doesn't matter where (stress energy or Einstein tensor) the cosmological constant comes from explain this discrepancy?
Wagon-wheel effect is a well-known optical illusion due to the persistence of vision. It happens when the spoke of a wheel rotates to a certain position after the duration of persistent vision. Depending on such position, the apparent wheel motion can have many appearances. However, is it possible to design a certain pattern of wheel entirely free from such an effect? Except for the trivial solution (no pattern or spokes at all).
I'm looking for a word that describes that feeling you get when somebody (of a group typically thought of having more power in society) brings up a group (typically thought of having less power in society: minority groups, women, LGBTQ) and you are hesitant to agree with them even though they are right (Like, in this hypothetical scenario they factually are, they're not twisting the facts or anything). It's kind of the same kinda gross feeling you probably got when you read "even though they are right" in a post loosely about racism from a stranger on the internet. This is the best explanation I can come up with. Is there such a word?
Inspired by a youtube video, i was trying to do the double slit experiment at home using a single hair and saw the interference pattern. Then i wondered what would happens with many hairs and when i shine the laser trough a bunch of them, these kind of patterns emerge. Here you can see a video: https://www.youtube.com/watch?v=utJyBEfwugE Sorry if the question is too generic, i'm not a physics student.
I want to confirm if I understand something correctly. We call the "high potential terminal" the positive side (cathode). Though, electrons move from negative to positive. Logically, electrons' potential energy is decreasing so the high potential terminal should be the negative side. In my opinion, from the electrons' perspective, the high potential terminal is the negative side, but since the current flows in the opposite direction, we always talk from the current's perspective, hence why we call the high potential terminal the positive side. Is this the correct logic?
I want to minimize the amount of unused space in a binpacking problem. I keep seeing binpacking being described as using the least amount of bins possible. Example (emphasis mine): assign each item to a bin such that number of total used bins is minimized https://www.geeksforgeeks.org/bin-packing-problem-minimize-number-of-used-bins/ Would minimizing the amount of bins guarantee the least amount of waste? And if so, is there a minimum amount of bins (based on the algorithm used, not necessarily the one from the above link) that we need to use before it is efficient? Or is binpacking "by default" efficient in minimizing waste?
I am building a database of sorts and came across this question. I am looking for a word that includes every region that is declared and made up by humans. So no natural regions like forests or continents, but regions that are generally associated with the people residing within its borders and other human-related stuff (laws, culture, goals...). Like Estonia, Tokio, EU... I found this similar question (Generic name for places like village, town and cities). But it's only about towns, cities etc.
In the sentence below, Greenland may not be as "green" as the name suggests. The verb "suggest" should preceed an object as it is a transitive verb, but in the sentence, there is none. In this case, should the second "as" be understood as some sort of relative pronoun though there is no noun? Or should it be understood as a comparative conjunction? If it is a comparative conjunction, is it ok to not have a direct object for "suggests"? And if something is omitted, what is it?
What would be the best books covering topics like Algebra, Geometry (Euclidean geometry) and Calculus? Which classics can be recommended (classics in the sense of historical works that have been widely disseminated throughout the history of mathematics, for example: Euclid's Elements)? I would like to have an overview of the main classics that influenced paradigms and changes in the history of mathematics (I understand that reading can be considered difficult, but I am willing to risk it). Objective: Historical Curiosity.
A sphere with a radius of one is put inside a cubical box with circular holes cut out such that the ball fits perfectly. The box and the sphere share the same volume; find the surface area of the box. I tried cutting the cube down the middle to get a square and a circle. I then tried to find the distance between the two points of intersection between the circle and square on one side of the square but hit a dead end. I then tried to find the volume of empty space in the box since that could help me find the volume of the protruding parts of the sphere and maybe lead to the answer but it led to no avail.
I was watching this video. It Showed that light ( green ) changes its color to red after incidence of light. I couldn't think of how this happens because light's color is dependent on frequency rather than wavelength and only the wavelength changes when light enters a new medium , according to these answers on whether light is depended on wavelength or frequency. So what explanation can be given for the change in color in a prism.
A student asked how to integrate tan x and he was trying while using integration by parts. I taught him the substitution method but he then asked why we can't use integration by parts. My immediate thought was it is possible just much more complicated but in trying it out, I can't seem to do so. Is it simply not possible to integrate tan x by parts? Attached are my workings for the substitution method and the failed attempt at avoiding substitution. Integration by substitution Trial of integration by parts
I am doing some work on the topic "Adjunction" and my current interest is to give some examples. I've wanted to provide some examples connected to some basic concepts from analysis on manifolds if such exists. What I thought maybe would work is the following: Tangent space functor and cotangent space functor Tensor product functor and multilinear form functor Pushforward and pullback of differential form I am not sure if any of these are indeed adjoint functors, so if they are I would appreciate any help in proving such a thing.
If you take an axiomatic view of Classical Mechanics and the concept mass as primitive in this context, you could derive from Newton's laws an operational way of determining masses simply by arbitrarily assigning a mass to an object and demanding momentum conservation in its interactions with other objects. But if there are interactions that increase as a function of distance, this method ceases to be practical. Does this imply that an axiomatic theory should include the prescription that forces decay with distance?
I'm trying to connect the calculations for the determinant I'm seeing and the idea that the determinant is a signed measure of the factor by which the volume bounded by the basis vectors of a vector space changes when those basis basis vectors are acted on by a linear transformation. Does anyone have a good way of connecting this geometric intuition with the way matrix determinants are computed, specifically with the "product of pivots" method I refer to in the title to this post? Thanks.
In a PhD thesis we have to write a preface wherein some significant theorems from the main body of the thesis are needed to be restated. The amstools or thm-restate package does not help me in this regard. In this package the restated theorem must appear after the original theorem is stated. Till date I am doing it manually. But then the problem is if I change something in the original theorem then the same change must be done in the restated theorem also but manually. Is there any efficient method to do it?