D'Alembers Principle - further explanation
Why is the d'Alembert's Principle formulated in terms of virtual displacements rather than real displacements in time?
Reputation does not update after community wiki is removed from a post, and does not match the value displayed in the reputation audit If votes were cast on a post while it was community wiki, and a moderator removes wiki from that post, the votes should count towards reputation again. However, while this is visible in a reputation audit, , and the reputation score needs to be recalculated to reflect the change.  Can someone fix this? Strange Pop-up appldnld.apple.com:80 I received a strange Pop Up message. The unsettling part is password will be sent in clear text.  Is my phone affected with any malware or app virus ? I'm attempting to cut a hole in a plane. I added a cylinder object, added the Boolean modifier to the plane, selected "cylinder" and "Difference", but no hole is made. The lower half of the cylinder just highlights, moving/deleting the cylinder reveals a hole-less plane.      How can i cut a hole in the plane? How did the Tesseract come to Earth from Asgard? How to deal with spaces in a variable Prove that if $(ab)^i = a^ib^i \forall a,b\in G$ for three consecutive integers $i$ then G is abelian Login screen resolution So I just installed Ubuntu 16.04 on my Dell XPS 13. When I get to the login screen it starts at 3200x1800 for a quick second, then I get a way lower resolution like 800x600 but as soon as I login it adjusts to 3200x1800. How would I get 3200x1800 permanently on my login screen? I didn't have this issue on 14.04. Add sort by relevance to search jobs In Careers 2.0, individuals can choose "search jobs" and sort by date posted, job title, and company name.  However, Careers 2.0 already knows what tags I'm proficient in, and knows the tags associated with the job postings.  A sort option, relevance, should be added so that jobs matching my skill set, as demonstrated on stack exchange, will float to the top. Unable to send e-mail. Contact the site administrator if the problem persists When my web form is filled and submitted, I get redirected to a page that says:     Thank you for submitting.   but theres a red warning box there that says:     Unable to send e-mail. Contact the site administrator if the problem persists.   I think its the SMTP server, but I don't know how to fix that. Can I run the python interpreter without generating the compiled .pyc files? Prove: if $|z|=1$ than $\frac{z+1}{z-1}$ is an imaginary number Prove: if $|z|=1$ than $\frac{z+1}{z-1}$ is an imaginary number    I have tried to look at $$\frac{z+1}{z-1}=\frac{z+1}{z-1}\cdot \overline{\frac{z-1}{\overline{z-1}}}=\frac{z+1}{z-1}\cdot \frac{\overline{z}-1}{\overline{z}-1}$$  But did not get far How to visualize a value resulted from math node,or just to know it. I tried the way of scaling this value to the scene size and then pick the color and get the value but I want more effective way to do this. Can I get an enters-the-battlefield effect out of a second legendary before I must sacrifice it? If I have a legendary creature out, and I make a copy of it (such as by enchanting it with  or making a ), do I get enters-the-battlefield effects from the creature before I have to sacrifice it to the legend rule? My local hackerspace has a CNC machine.  I can give them my Gerbers and they can print out the PCB.  The machine does not plate VIAs.  I need to do this after the CNC machine is finished.  What is the best process and materials to use? When I double-click on a script in Nautilus to run it, the script just opens in my text editor with no option to run it. Using Nautilus, how do I run executable text files and/or scripts? What conditions need to be fulfilled to enter the Schengen zone visa free? Disk brakes severely reduced in power after replacing bearings Consolidate tag wiki excerpt and body contents with regards to suggested edits At the moment, in major part because they are two separate post objects in the system, the excerpt and the body of a tag wiki count as two separate posts with regards to suggested edits in the queue. Mechanically, this is sane, but when it comes to handling the actual queue, it can be confusing. A body edit might consist of little more than a bed of links, which looks bad. But then an excerpt is shown that includes the rest of the data, and since excerpts can be included on the actual wiki page, it makes a lot more sense when they're taken in the same space.  And this is how they are composed, too. The actual edit interface for working on tag wikis has both the excerpt and the body on the same page. In a sense, the excerpt behaves a lot like the "title" of the wiki, if we make a parallel to normal post edits.  Thus, my suggestion (which is to say a suggestion that I repossessed from Robert Cartaino) is that when suggested edits are reviewed for tag wikis, that they be presented in a single unit, treating the excerpt the same as how a title is treated in a question edit. This way, relevant information that is crossed between the two isn't lost because they are reviewed separately. Several times now I have inadvertently lost the .tex file that generated a PDF file with pdflatex. Given what I know of the internal structure of PDF files, it should be possible to embed a text file containing the original LaTeX file into the PDF file so that it can be extracted later.   I am aware of no technology for doing this, but perhaps you are. Does anybody have something like this? Column and row padding in tables How do you guys go about controlling column padding in tables?   Update  To clarify, I'm looking for a way to control both vertical and horizontal padding. So, if I had a simple table like in the following code snippet, I could pad the columns and make them look a bit less... ugly. :P   \begin{tabular}{|l|l|}     \hline     column 1 &amp; column 2 \\      \hline     I really would like this less &amp; crammed\\     \hline \end{tabular}   I tried this by using the command \vspace but it leaves gaps in the vertical lines.