Most of the material when heated turn red or orange or yellow, why materials don't have a tone green or blue when heated high.
Why don't metals glow from red to yellow to green to blue etc.? Why only red, then yellow and then white? Shouldn't all wavelengths be emitted one by one as the temperature of the metal increases?   If some metals do glow at with different colours, could you give me examples of such metals and the reason why this happens in specific cases?
I understand that when I press and release the power button on the top of my iPhone or iPad, it stays on but turns off the screen.  Whereas if I press and hold the power button, a "slide to turn off" control appears on the screen.  Sliding this, as I was told, does turn the unit off, but it does so by suspending the RAM to disk (flash memory, actually.) So, when turning on the iPhone or iPad, it isn't so much rebooting the OS as it is resuming it from flash storage.  How to force the OS to completely reboot on these devices? Allow cross-site queries in data explorer Is it possible to boot Ubuntu using the Windows bootloader? As noted by many people, Windows 8's UEFI requirements might will won't get in the way of installing Linux (or whatever), as the replacement bootloader will also need to be signed somehow. Some systems All systems will let you disable the signature requirement, but the feature might be hidden to disable or you might not be willing to give up on the benefits of a secure bootloader.  Is it necessary to replace the bootloader in the first place? To keep ourselves to software that's gone golden, how can I install Ubuntu 11.04 using Windows 7's own bootloader? The quotient norm on $\ell^{\infty}(\mathbb{N}) / c_0 (\mathbb{N})$ is given by $\limsup_{n \in \mathbb{N}} |x_n|$. I try to show that the norm on the quotient space $\ell^{\infty}(\mathbb{N}) / c_0 (\mathbb{N})$ is given by $\limsup_{n \in \mathbb{N}} |x_n|$, where $x = (x_n)_{n \in \mathbb{N}} \in \ell^{\infty} (\mathbb{N})$. My attempt is the following:     By definition, the quotient norm $\| \cdot \|_{\ell^{\infty} / c_0}$ is defined as   $$ \| x + c_0 (\mathbb{N}) \|_{\ell^{\infty} / c_0} = d( x + c_0 (\mathbb{N}), 0 + c_0 (\mathbb{N}) ), $$   which can be re-written as    $$ \| x + c_0 (\mathbb{N}) \|_{\ell^{\infty} / c_0} = \inf \{ \| x + y \|_{\infty} \; | \; y \in c_0 (\mathbb{N}) \}. $$   Since $0 = (0,0,...) \in c_0 (\mathbb{N})$, it follows that   $$ \| x + c_0 (\mathbb{N}) \|_{\ell^{\infty} / c_0} \leq \| x \|_{\infty} = \sup_{n \in \mathbb{N}} |x_n|. $$   I thought about using Bolzano-Weiserstrass' Theorem at a certain point, but I am not sure how to obtain the wished equality from here.    Any help is appreciated. Thanks in advance. Make Windows 10 stop installing driver software automatically Proving “The sum of $n$ consecutive cubes is equal to the square of the sum of the first $n$ numbers.” This   states:      Example $\boldsymbol 3$. The sum of consecutive cubes. Prove this remarkable fact of arithmetic: $$1^3 +2^3 +3^3 +\ldots +n^3 =(1 +2 +3 +\ldots +n)^2.$$   “The sum of $n$ consecutive cubes is equal to the square of the sum of the first $n$ numbers.”      In other words, according to Example $1$: $$1^3 +2^3 +3^3 +\ldots +n^3 = \frac{n^2 (n+1)^2}{4}.$$   Should: $$1^3 +2^3 +3^3 +\ldots +n^3 = \frac{n^2 (n+1)^2}{4}$$ not be: $$1^3 +2^3 +3^3 +\ldots +n^3 = \frac{n^3 +(n + 1)^3}{2^3}$$ as everything in the left-hand side is cubed? Regex for splitting a string using space when not surrounded by single or double quotes Do you have to want to hurt someone for the cruciatus curse to work? I am getting a Too many SOQL queries: 101 error on a trigger when I am trying to deploy another trigger.  I am posting the trigger which is causing the error.  trigger rollupAccountShowings on Account (before insert, before update) {    if (trigger.isinsert) {       for (Account a:Trigger.new){           a.No_of_Viewings__c = 0;        }    } else {      for (account a : [select                   id,                  (select id from pb__Showings__r)                  from account                   where id in:trigger.new LIMIT 1]) {           trigger.newMap.get(a.id).No_of_Viewings__c = a.pb__Showings__r.size();      } }   Can anyone correct me where I have gone wrong and suggest me the changes.  Thanks Is this true?  If $A$ and $B$ are sets, then $A=\emptyset $ if and only if $B = A \bigtriangleup B$.  If $A=\emptyset$ then $B=\emptyset$ too?  Could someone help me please? After swapping the positions of the hour and the minute hand, when will a clock still give a valid time? Is a citizen of Canada required to apply for a US visitor visa after visiting Iran? Under new rules, non-US citizens from Visa Waiver Program countries who have visited Iraq, Syria, Iran, Sudan, Libya, Somalia, or Yemen are required to apply for a proper visa because they are no longer eligible for the VWP.   Does the above apply to citizens of Canada also? Canada is not a Visa Waiver Program country, but instead Canadian citizens can enter the US visa-free. If a Canadian citizen has visited Iran for example, is the entry procedure to the US any different?  I have looked through  but that page does not mention Canada. Awesome symbols and characters in a bash prompt I just ran across a screenshot of someone's terminal:    Is there a list of all of the characters which can be used in a Bash prompt, or can someone get me the character for the star and the right arrow? Show the commutator subgroup of $S_{n}$ is $A_{n}$ for $n \geq 5$ Show that for $n \geq 5$, the commutator subgroup of $S_{n}$ is $A_{n}$ for $n \geq 5$.     I'm not sure on how to handle this problem. I know that the commutator subgroup $G'$ will consist of products of commutators $[\sigma_{i}, \tau_{i}]$ for permutations $\sigma_{i}, \tau_{i} \in S_{n}$. However, I don't know where to start. What would be the best way to approach this? What part of speech is "back" in "put the book back on the table"? Put the book back on the table.   I'm having trouble. I think it is a preposition. When to use 'which' or 'in which' or 'that' (as relative pronouns)? I am confused about when to use:  'which' vs 'in which' vs or 'that'?    Would you please explain it as a writing rule? Here I have an example:       Authors reported shortened growth period and slower radial growth rate for low soil water potential which is directly attributed to the decrease in water potential, rather than to the constraints on carbon availability. How to change Gnome-Terminal title? I have several instances of terminals running in my working environment, what I would like is to set a specific title for each one, in order to have a clear idea what purpose the specific terminal serves i.e. Apache, editing_ini, postgres etc...  Of course from the command line. Why does the following code in C work?  const char* str = NULL; str = "test"; str = "test2";   Since str is a pointer to a constant character, why are we allowed to assign it different string literals?  Further, how can we protect str from being modified?  It seems like this could be a problem if, for example, we later assigned str to a longer string which ended up writing over another portion of memory.  I should add that in my test, I printed out the memory address of str before and after each of my assignments and it never changed.  So, although str is a pointer to a const char, the memory is actually being modified.  I wondered if perhaps this is a legacy issue with C? Im using a program called Daisy Disk to see what is taking up space in my Mac and I find that the /cores directory is taking up 77gb.   Is that a problem? Can I get rid of it to regain the space? What does (obj.length === +obj.length) compare?