How can I use linebreak inside \coordinate, in tikz?
Manual/automatic line breaks and text alignment in TikZ nodes
If a black body is a perfect absorber, why does it emit anything? I'm trying to start understanding quantum mechanics, and the first thing I've come across that needs to be understood are black bodies. But I've hit a roadblock at the very first paragraphs. :( According to :     A black body (also, blackbody) is an idealized physical body that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence.   OK, that's nice. It's an object that absorbs (takes in itself and stores/annihilates forever) any electromagnetic radiation that happens to hit it. An object that always looks totally black, no matter under what light you view it. Good. But then it follows with:     A black body in thermal equilibrium (that is, at a constant temperature) emits electromagnetic radiation called black-body radiation.   Say what? Which part of "absorbs" does this go with? How can it absorb anything if it just spits it right back out, even if modified? That's not a black body, that's a pretty white body if you ask me. Or a colored one, depending on how it transforms the incoming waves.  What am I missing here? What is Java's answer to WPF? I'm mostly a .Net person at the moment, but I've been playing with Java some lately-- exploring what's out there.  Now I'm looking for the Java equivalent for WPF.  I know I could find an OpenGL library or two out there, but that's not really as rich or simple as the WPF system. The positive integer solutions for $2^a+3^b=5^c$ What are the positive integer solutions to  the equation     $$2^a + 3^b = 5^c$$    Of course $(1,\space 1, \space 1)$ is a solution. Punctuation in an indirect quotation Consider the brief passage:     "I love your work, but calling you 'the artist' {1} just doesn't seem to be   cutting it anymore. What shall I call you?"      "OK. Call me George." {2}   So my instincts tell me to put {1} in single quotes as opposed to no punctuation (or perhaps even italics) but to do the opposite for {2}. Is this right? Why?  Let me expand this one further iteration:     "Wow, that's a great name, especially with this crowd. Maybe for your next book    you should call yourself Ringo."{3} Integral $ \int_{-\infty}^{\infty}\frac{x^{2}}{\cosh\left(x\right)}\,{\rm d}x $ I need to compute the improper integral $$ \int_{-\infty}^{\infty}\frac{x^{2}}{\cosh\left(x\right)}\,{\rm d}x $$ using contour integration and possibly principal values.  Trying to approach this as I would normally approach evaluating an improper integral using contour integration doesn't work here, and doesn't really give me any clues as to how I should do it. This normal approach is namely evaluating the contour integral $$ \oint_{C}{\frac{z^2}{\cosh\left(z\right)}\mathrm{d}z} $$ using a semicircle in the upper-half plane centered at the origin, but the semicircular part of this contour integral does not vanish since $\cosh\left(z\right)$ has period $2\pi\mathrm{i}$ and there are infinitely-many poles of the integrand along the imaginary axis given by $-\pi\mathrm{i}/2 + 2n\pi\mathrm{i}$ and $\pi\mathrm{i}/2 + 2n\pi\mathrm{i}$ for $n \in \mathbb{Z}$. The residues of the integrand at these simple poles are $-\frac{1}{4}\mathrm{i}\pi^{2}\left(1 - 4n\right)^{2}$ and $\frac{1}{4}\mathrm{i}\left(4\pi n + \pi\right)^{2}$, so that even when we add up all of the poles, we have the sum $4\pi^{2}\mathrm{i}\sum_{n = 0}^{\infty}\,n$, which clearly diverges.  Any hints would be greatly appreciated. Terminal method of formatting storage drive I want to know how to format a storage drive from the terminal. Helpful things to provide in the answer would be often used options for commands and base knowledge that one can use to extrapolate future uses. Specifically I would like to know how to format in the different file systems such as NTFS, FAT32, EXT4, etc. Information on how to partition the drive via terminal is also wanted.  I am trying to format a high capacity external hard drive (EHDD) into NTFS - from the terminal.   I know I can use gparted for this as well as other GUI programs, but I still want to now how to do it from the terminal. "I think him to be about 50" or "I think he is about 50"? NIST randomness test p values I have a binary sequence of length $2^{20}$. I am using the NIST statistical test, assess.   What should be taken for ./assess and  How many bitstreams? in this test? In the final Analysis report, what p-values should be there to pass this test? How can I fix a 404 Error when using a PPA or updating my package lists? Does iOS 7 cellular tethering limit the number of WiFi clients? I'm looking on Apple's site and can't find any published limits on how many clients can connect to one iPhone / iPad with cellular tethering enabled in the US.  Setting aside the obvious limit where 1,000 devices would overwhelm the data connection in practice if they all want data at the same time, is there a hardware or software limit of perhaps 5 or 10 devices that can connect to one device over WiFi? Show that any prime divisor of $x^4+x^3+x^2+x+1$, with $x\in\mathbb{N}$, is $5$ or $1$ mod $5$ We can write the "polynomial" as follows: $$x^4+x^3+x^2+x+1=\frac{x^5-1}{x-1}.$$ For even $x=2y$, we have that $x^5-1=(2y)^5-1=32y^5-1\equiv1$ mod $5$.  For odd $x=2y+1$, we have that $(2y+1)^5-1\equiv_532y^5\equiv2$ mod $5$.  I find it hard to believe my computations above. I guess this makes me rather clueless. I was hoping there was some way out with Legendre symbols. Any help is appreciated. Do particles in a sound wave ever move transversally? I'm trying to visualize how sound waves work and I was curious about something.   So sound moves in longitudinal waves, which I think I understand.  There is a really good  explaining this.  In the video the air particles are depicted as moving from left to right (longitudinally). But do they ever move up and down even a little bit? Are they on some kind of fixed axis where they can only move longitudinally and never move even the slightest bit in a vertical direction? Calculating the peak voltage of a zener diode output I have a problem with this homework, I have to calculate the peak voltage of the output after stabilizing with a zener diode.  My Input Voltage is Vin = 5V + 0.7Vsin (2pif*t) with f=10kHz  My circuit is a simple regulator with no load resistor. The series resistance is 82 Ohms, Zener voltage is 3V, max. current through the diode is 33.3mA. How can I calculate the peak output ? My problem is the offset created by 5V, wouldnt the Zener voltage be reached immidiately with this configuration ?         &ndash; Schematic created using The "Satellite Paradox": Twin paradox in orbiting satellites I want to simply eliminate the effect of acceleration, which is the cornerstone in resolving the traditional twin paradox, through the following thought experiment: Assume twins $A$ &amp; $B$ are located in the same orbital height, far away from the surface of a massive planet, on a long concrete column at rest WRT the planet. A rapid explosion that happens between the twins makes them orbit the earth with a high velocity, say, $0.6 \ c$, in the same orbital path but in different directions. According to relativity, since the orbiting satellites are completely inertial frames, each twin attributes a variable time dilation to the other one, and each twin expects the other one to be younger. Nonetheless, these twins are automatically reunited after traveling half of the orbit's circumference without being affected by additional accelerations. Which twin is younger in this case? Indeed, If each twin sees the other's clock as running slow all along the way, how can the clocks agree when they meet? For this configuration:  The acceleration due to the explosion does not affect the twins' clock rates since it occurs abruptly in the same place on the column where the twins are located back-to-back. The clocks have been synchronized just before the explosion.  The traditional gamma factor, attributed to one twin from the viewpoint of the other, is variable because the resultant velocity of one twin complying with the relativistic velocity addition is a variable measured from the viewpoint of the other one. However, whether or not the corresponding time dilation is varying, each twin anticipates the other one to be younger. There is no breaking of symmetry!  The $g$-field of the planet has nothing to do with orbiting satellites since they are inertial, and thus GR corrections are not inserted. (Remember the GPS settings!) How to select an element whose id is dynamic and keeps changing There is a type and search drodown which will appear after user type in the value. I need to click on the dropdown which contains the name of the drop down field.   The problem here is that there is no unique attribute present (No unique class, no unique name) &amp; the id keeps on changing after every login so cannot take id also. What are some good ways to showcase someone's portfolio work online? I've designed for a campaign a duo of rogues. My character is as , and his follower is a Knife Mistress. Couple of question about them. Our party is about to ambush several . My Sniper will hide near their camp, and shoot the weakest one when fight begins. His follower will then rush the troll and slice him in several pieces. My Sniper has the Bleeding attack feat:  Bleeding Attack (Ex) Benefit: A rogue with this ability can cause living opponents to  by hitting them with a sneak attack. This attack causes the target to take 1 additional point of damage each round for each die of the rogue's sneak attack (e.g., 4d6 equals 4 points of bleed). Bleeding creatures take that amount of damage every round at the start of each of their turns. The bleeding can be stopped by a DC 15 Heal check or the application of any effect that heals hit point damage.  Emphasis mine. Thus, a normal enemy would bleed every turn, until he get cleaned of the bleeding effect. However, troll have a special ability, which is  5 (acid/fire)  Regeneration (Ex) A creature with this ability is difficult to kill. Creatures with regeneration heal damage at a fixed rate, as with , but they cannot die as long as their regeneration is still functioning (although creatures with regeneration still fall unconscious when their hit points are below 0). Certain attack forms, typically fire and acid, cause a creature’s regeneration to stop functioning on the round following the attack. During this round, the creature does not heal any damage and can die normally. The creature's descriptive text describes the types of damage that cause the regeneration to cease functioning.  So, the troll will automatically get rid of the bleeding effect during his first turn. My question is: Does the bleeding effect apply before the regeneration, or get neglected, because the troll will heal during his turn? Am I right to assume that, Bleeding attack effect getting triggered at the beginning of the troll turn, it will deal him the damages before the wounds heals? Temperature and kinetic energy of molecules I was wondering if temperature is related to the average translational kinetic energy of the molecules then why does the average kinetic energy of say a moving object not affect the temperature? What is the mechanism regarding these vibrational motions that imparts temperature. Also do a gas and liquid at the same temperature possess the same kinetic energy? and a heavier molecule traveling at the same speed as a lighter molecule will have a greater temperature? Make Chrome always execute with flags, for eg., directly opening an HTML file I want to run Chrome with a given set of flags, always  I created a shortcut and added the flag to it in the following way, so my target of the shortcut says:  C:\&lt;application-path&gt;\chrome.exe --user-data-dir=D:\Chrome   But when I double click an HTML file, or if any other application triggers Chrome, it looses the flag value. The result - A new chrome window opens with Default profile directory.  I want to make the flag permanent, so that its active irrespective of however Chrome executes.  I tried changing the following registry key:  HKEY_CLASSES_ROOT\ChromeHTML\shell\open\command   It was this earlier:  "C:\&lt;application-path&gt;\chrome.exe" -- "%1"    I changed to following attempts which did not work:  1. "C:\&lt;application-path&gt;\chrome.exe" -- "%1" --user-data-dir=D:\Chrome 2. "C:\&lt;application-path&gt;\chrome.exe" -- "%1" -- "user-data-dir=D:\Chrome" 3. "C:\&lt;application-path&gt;\chrome.exe" -- "%1 user-data-dir=D:\Chrome"   Conclusively, when I try to open a link from any application, it doesn't open in my current Chrome as a new tab, rather opens a new Chrome window with no plugins and extensions since its from other directory.  Why I have changed my default directory? - because the OS drive was getting low on memory due to heave Chrome caches and apps. Comment authors are not getting migrated