Where does the information about the direction of the emission of the Photoelectron come from? Does it get it from the incoming Photon? I have seen a picture on wikipedia-page of the photoelectric effect, where it almost looked like if the angle of the emission of the Photoelectrons were the same as the angles from the incoming Photons. Is there some "law" which describes why and how the Photoelectrons are emitted at a certain angle like there is for the reflection of light when it hits a reflecting surface in optics?
In the experiments for photoelectric emission, the light is incident on one face of the emitting plate, for example the anode, when determining the stopping potential. The electrons are emitted by this face of the plate. Why are the electrons emitted in the direction of the incident light, and not opposite to it?  I have read a little about photons (the key words being, a little), and from what i gather, they have an intrinsic momentum $p=h/\lambda$, which is transferred entirely to the particle that absorbs it (along with the energy $h\nu$). This should imply that the electrons try to move further into the cathode, and not escape it! What is the fault in the reasoning?  Thanks!
The + vowel letter I've been told that when "the" is proceeded by a vowel sound, like "apple" or "hour", it's pronounced as "thee" and not as "thu".  But after listening to a couple of songs, I noticed that sometimes this "rule" is not followed. Take for example the two Katy Perry's songs, "Roar" and "The one that got away". In the first she sings "I got thee eye of thu tiger", but in the second she sings "Thu one that got away".  I don't know if it was sang this way to better suit the song melody (I understand nothing about those techniques), but I got confused. What's the correct pronunciation?  Thanks in advance. Screen brightness isn't taking effect on a Lenovo Z570 My Lenovo Z570 has two GPU's, nVidia and Intell. Brightness control has no effect what so ever over the screen brightness, and because I've had some major issues in the past when I was trying to fiddle with nVidia drivers and settings, and I wanna be cautious now. I haven't find similar questions referring 14.04 LTS with similar configuration as mine.   I've read that it could be fixed by adding/changing content in xorg.conf but when I run  sudo gedit /etc/X11/xorg.conf   the file comes out to be absolutely empty. What do I need to do, what do I need to add to it and not get my laptop screwed with a black screen again? How to shop for a lens filter? What should I consider when shopping for a lens filter?    I see filters that range from $15 to $115 and more.  What are the differences between the $15 and the $115 filter?    I'm asking in the generic sense but if you need specifics, I'm looking to buy a UV filter and a polarizing filter for a Panasonic GF1 w/ 20mm pancake lens.  EDIT: I've read some of the other posts and some refer to multi-coating but doesn't explain what is this and why it matters.  What I've gathered from reading related posts is that price is generally the only indication of quality in the case of choosing a filter.  Is this right? How does the Deposit-User work? Sending file of custom python script with all parameters for popup interface already defined? I have a python script in ArcGIS 10 that when clicked, has a popup for a user to choose parameters. I would like to send this file to someone else. While I could send them the python code and have them setup the parameters - this method repeats work I have already done.   I would like to send someone one file that contains all of this information so they can just recieve my file, add it to a toolbox, and then have it all work. I am wondering where the file resides that has both the python code and parameters / what is the export process/ file type I should be looking at? (All the searches I do for "export script" seem to refer to exporting a model to python code...) I've looked through a number of the "Vote too old to be changed" questions, but I think this one's different.  I gave a downvote to an answer I thought had a critical defect, and I left a comment describing the defect. The answer was edited to satisfy my criticism, but it was done within the short grace period where edits aren't recorded as such. When I try to cancel my downvote I get the error - "Your vote is now locked in unless this answer is edited" - but it was edited!  In reference to this answer: I need to find a period-3 orbit for a tent map defined by $$T(x)=\begin{cases}2x &amp; 0\le x\le0.5 \\[2ex] 2-2x &amp;0.5 &lt; x \le 1 \end{cases}$$  So, what is a fast and efficient way of finding it? I only know how to do it by guessing-and-checking. For example, I picked a random point, $x = \frac{2}{7}$ and found that $$T\left(\frac{2}{7}\right)=\frac{4}{7}\\[4ex]T\left(\frac{4}{7}\right)=\frac{6}{7}\\[4ex]T\left(\frac{6}{7}\right)=\frac{2}{7}$$ which is a period-3 orbit. Is there any better way of finding a period-3 orbit , more specifically, a period-3 point? Error handling in C code When using sudo powers and calling gedit the top level menu with File Edit View Search Tools Documents Help is missing.  If I create user ID root and sign in once and call gedit will it create the necessary user configuration files that might fix this?  Will this also make the annoying error messages go away whenever I use sudo, gksu or pkexec as a regular user with elevated privileges togedit ?  Will there be other benefits with Nautilus and other Gnome derivative Ubuntu applications?  NOTE: by sudo powers you can google pkexec gedit 3.5k hits, gksu gedit 40k hits or sudo gedit 500k hits. I'm in the minority using the first method but I believe it will become the standard in Ubuntu 17.04.    June 12, 2017 Update Here are a list of errors you get when using pkexec gedit:  (gedit:13003): Gtk-WARNING **: Calling Inhibit failed: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.gnome.SessionManager was not provided by any .service files  ** (gedit:13003): WARNING **: Set document metadata failed: Setting attribute metadata::gedit-spell-enabled not supported  ** (gedit:13003): WARNING **: Set document metadata failed: Setting attribute metadata::gedit-encoding not supported  ** (gedit:13003): WARNING **: Set document metadata failed: Setting attribute metadata::gedit-position not supported   On this  there is a commitment to fix these distracting messages as of June 5, 2017. No indication is given for when the fix will be upstream nor if the functionality will be implemented or the error messages will simply disappear.  Note the bug report was filed over a year ago and over that time it only effects 18 people. Why does a find field value in one application show up in a the find field of another application? On my MacBook Pro I have found that several applications seem to share the value for a find.  For example, I searched 'applestackexchange' in Safari's unified address bar, then I switch to Xcode and click into a Find field.  The first word of my search in Safari then appears there.  iTerm2 and Sublime Text 2 also seem to participate in this sharing.  Running latest Mountain Lion on  a 2012 MBP. Generating samples from singular Gaussian distribution Let random vector $x = (x_1,...,x_n)$ follow multivariate normal distribution with mean $m$ and covariance matrix $S$. If $S$ is symmetric and positive definite (which is the usual case) then one can generate random samples from $x$ by first sampling indepently $r_1,...,r_n$ from standard normal and then using formula $m + Lr$, where $L$ is the Cholesky lower factor so that $S=LL^T$ and $r = (r_1,...,r_n)^T$.  What about if one wants samples from singular Gaussian i.e. $S$ is still symmetric but not more positive definite (only positive semi-definite). We can assume also that the variances (diagonal elements of $S$) are strictly positive. Then some elements of $x$ must have linear relationship and the distribution actually lies in lower dimensional space with dimension $&lt;n$, right?  It is obvious that if e.g. $n=2, m = \begin{bmatrix} 0 \\ 0 \end{bmatrix}, S = \begin{bmatrix} 1 &amp; 1 \\ 1 &amp; 1\end{bmatrix}$ then one can generate $x_1 \sim N(0,1)$ and set $x_2=x_1$ since they are fully correlated. However, is there any good methods for generating samples for general case $n&gt;2$? I guess one needs first to be able identify the lower dimensional subspace, then move to that space where one will have valid covariance matrix, then sample from it and finally deduce the values for the linearly dependent variables from this lower-dimensional sample. But what is the best way to that in practice? Can someone point me to books or articles that deal with the topic; I could not find one. The story is basically told from an alien's point of view. Essentially they observed us from far off, deemed us as violent and a danger to the universe, and set course (asteroid or something) to kill us. They kept observing and saw all the art and beauty we created and realized we were actually not so bad, but by then they couldn't stop it. So it was sort of also an apology letter to Earth in the end.  First read it like a year ago online and I can't find any trace of it anymore, nor can I recall the site it was on. Anyone know what short story this is? To make a JavaScript class with a public method I'd do something like:  function Restaurant() {}  Restaurant.prototype.buy_food = function(){    // something here }  Restaurant.prototype.use_restroom = function(){    // something here }   That way users of my class can:  var restaurant = new Restaurant(); restaurant.buy_food(); restaurant.use_restroom();   How do I create a private method that can be called by the buy_food and use_restroom methods but not externally by users of the class?  In other words, I want my method implementation to be able to do:  Restaurant.prototype.use_restroom = function() {    this.private_stuff(); }   But this shouldn't work:  var r = new Restaurant(); r.private_stuff();   How do I define private_stuff as a private method so both of these hold true?  I've read  a few times but it doesn't seem like "private" methods can be called by public methods and "privileged" methods can be called externally. I often see tutorials online that connect various commands with different symbols. For example:  command1 |  command2 command1 &amp;  command2 command1 || command2     command1 &amp;&amp; command2   Others seem to be connecting commands to files:  command1  &gt; file1 command1  &gt;&gt; file1   What are these things? What are they called? What do they do? Are there more of them?    . When do I need to invoke \phantomsection? Putting a piece of code in between two html tags in Solaris On a solaris HTML file, how do I insert between an html tag and head tag? through bash scripting.  I have an html tag that looks like this:  &lt;html xmlns="http://www.w3.org/1999/xhtml" xmlns:arf="http://scap.nist....-format/1.1" lang="en"&gt;   I want to insert a script written in text file, inside this 'SOLARIS' run HTML file, AFTER the long &lt;html....&gt; tag and BEFORE &lt;head&gt; tag, meaning BETWEEN the two tags, How do I do that?  I want to test using the bash commands to do it for one file at a time as well as multiple file in a folder directory. Will I have to use the folder path in my BASH code? Will I have to use FOR loop or interation in my BASH code? What would be the right code. Note: it is SOLARIS run html file not LINUX one. The name of my HTML file is report.usc20.html.  These are the lines of script that I want to use that are in my backbutton_and_scroller_script.txt file:  &lt;div id="button"&gt;&lt;a href="http://.....index.php"&gt;Back To The Hardening Page&lt;/a&gt;&lt;/div&gt; &lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"&gt;&lt;/script&gt; &lt;script type="text/javascript" src="http://arrow.scrolltotop.com/arrow78.js"&gt;&lt;/script&gt; &lt;noscript&gt;Not seeing a &lt;a href="http://www.scrolltotop.com/"&gt;Scroll to Top Button&lt;/a&gt;? Go to our FAQ page for more info.&lt;/noscript&gt; Setup SunFire 440 Raid Configuration This is rather difficult to describe with fancy pictures with red circles but it's easily reproducible.  Whenever I click Leave Closed in the re-open queue on MSO the "nominate this question for re-opening" pop-up appears. I normally press escape out of shock and a leave closed vote is recorded.  This is the latest review it's happened to me on:   You can also test it on , I clicked reopen this time and a leave closed vote was recorded but I also got a red popup stating that an error had occurred.  This is also occurring when the Edit &amp; Reopen button is clicked, the edit box opens for a second before being overridden by the popup. Now, that Adobe has stopped issuing new releases for Linux desktops, the only option for users is to use Google Chrome, for those who want to use the latest Flash updates. I use Chromium. Is there any way to get Chromium use the Flash from Google Chrome? The reason I as this question is that I have noticed both these browsers run in the background, so technically, the browsers' plugins are available to use. How do you associate the .exe file extension with a program in Windows?