How to calculate how much wight a motor can lift?
What DC motor specs do I need to lift a weight with certain gear configuration
How do I prevent widow/orphan lines? What are tag synonyms and merged tags? How do they work? What is the correct way to show tiered possession? When there are multiple places where possession is shown, how are the words structured?  A few examples:   Greg's son's laptop is on fire. Mary's friends' boat is sinking. Thomas's neighbor's cat ate a mouse. Apple's Stock App's stats are useful. Microsoft's Xbox 360's games are fun.   Are these the correct ways to express possession? I have an Asus UL30JT. It has Nvidia Optimus technology which I am not really interested in. I currently rarely use this laptop with it being connected to power. And I want to be able to play video at high res, play games and do some OpenCL coding.  In the BIOS I switched it to NVIDIA only (non windows 7). Previously, this worked just fine, using the nvidia driver.  After upgrading everything was broken. I have added nomodeset and blacklist.nouveau=1 as kernel options. The nvidia drivers install without error. However they are not found/used.  jockey-text -l kmod:nvidia_310_updates - nvidia_310_updates (Proprietary, Enabled, Not in use) kmod:nvidia_304_updates - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use) kmod:nvidia_313_updates - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use) kmod:nvidia_310 - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use) kmod:nvidia_304 - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use)   Trying to load the module manually fails as well.  sudo modprobe nvidia FATAL: Module nvidia not found.   Xorg.0.log show the following:  [    12.028] Loading extension GLX [    12.028] (II) LoadModule: "nvidia" [    12.037] (WW) Warning, couldn't open module nvidia [    12.037] (II) UnloadModule: "nvidia" [    12.037] (II) Unloading nvidia [    12.037] (EE) Failed to load module "nvidia" (module does not exist, 0) [    12.037] (==) Matched nvidia as autoconfigured driver 0 [    12.037] (==) Matched nouveau as autoconfigured driver 1 [    12.037] (==) Matched vesa as autoconfigured driver 2 [    12.037] (==) Matched modesetting as autoconfigured driver 3 [    12.038] (==) Matched fbdev as autoconfigured driver 4 [    12.038] (==) Assigned the driver to the xf86ConfigLayout [    12.038] (II) LoadModule: "nvidia" [    12.038] (WW) Warning, couldn't open module nvidia [    12.038] (II) UnloadModule: "nvidia" [    12.038] (II) Unloading nvidia [    12.038] (EE) Failed to load module "nvidia" (module does not exist, 0) [    12.038] (II) LoadModule: "nouveau" [    12.039] (WW) Warning, couldn't open module nouveau   I have installed the kernel headers, of the correct kernel. I verified that the kernel options are in the grub configuration. I have purged all nvidia packages and tried to reinstall (multiple times...)  Currently I am at a loss. I have checked the following question:  But nothing there worked for me. What does % do to strings in Python? I was wondering how light or any electromagnetic radiation can be "absorbed" if it consists of electric and magnetic fields. For example if there is a charge at point A, and the  light reaches point A, it will cause that charge to move depending on the value of the electric field. However, why wouldn't this electric field continue on and influence others particles everywhere else? For example, if you have a static charge creating an electric field, then if you put a charge at point A it will feel its effects and then if you bring a charge at another location B it will also feel its effects, namely it will not have been absorbed. Please shed some light on this. Thanks  edit: Does this mean the electron that absorbs this light moves in such a way that it creates an electric field of its own canceling the initial one? Or am I way off? I am having trouble understanding the estimation of an AR process. In some textbooks, the AR(1) process is defined as follows: $y_{t}=\theta y_{t-1}+ϵ_t$ (which does not contain a constant). So the OLS estimator is biased. I am confused about the cause of the bias. It is explained that $y_{t-1}$ is dependent on $ϵ_{t-1}$ although it is independent of $ϵ_t$. However in linear regression, if the equation does not contain a constant, we cannot make sure the expectation of disturbance is zero. So the OLS estimator is bias without a constant. Does it mean that the OLS estimator is unbiased if I add a constant in AR process? What are the pros and cons of the leading Java HTML parsers? Algorithm for determining random events I'm struggling with coming up with an elegant solution to generating random events in the game that I'm working on.  Say there are 4 classes of events that can happen, with varying events in those classes that may occur.  So something along the lines of   main_events = {"common event", "not so common event", "somewhat rare event", "rare event"} sub_events[0] = {"common event 1", "common event 2",..} ...   I have a somewhat kludgey solution in place that first just has a random number generated between 0 and 100, and if the number falls within a given range then a main event will be triggered.  Then I'll do another random roll to see which sub event occurs.  Is there a better solution than something along these lines?  Like I mention, it doesn't feel very elegant, and I'd like to make it easily expandable for the addition of future events. Can an integrity check be run against a USB boot disk? Is there anything in the physics that enforces the wave function to be $C^2$? Are weak solutions to the Schroedinger equation physical? I am reading the beginning chapters of Griffiths and he doesn't mention anything. Lets say I have a domain already, for example www.automobile4u.com (not mine), with a website fully running and all.  The title of my "Website" says:    &lt;title&gt;Used cars - buy and sell your used cars here&lt;/title&gt;   Also, lets say I have fully SEO the website so when people searching for the term buy used cars, I end up on the second or first page.  Now, I want to end up higher, so I go to the google adwords page where you can check how many searches are made on specific terms.  Lets say the term "used cars" has 20 million searches each month.  Here comes the question, could I just go and buy that domain with the search terms adress, in this case www.usedcars.com and make a redirect to my original page, and this way when people search for "used cars", my newly bought domain name comes up redirecting people to my original website (www.automobile4u.com)?  The reason I believe this benefits me is because it seems search engines first of all check website adresses matching the search, so the query "used cars" would automatically bring www.usedcars.com to the first result right?  What are the downsides for this?  I already know about google spiders not liking redirects, but there are many methods of redirecting...  Is this a good idea generally? This one never ceases to confuse me. When to use 'such as' and when to use 'like' while giving examples? Is there any clear rule?        Metros like Mumbai, Delhi and Karachi are unsafe after dark.    Metros such as Mumbai, Delhi and Karachi are unsafe after dark.       (Before anyone points out, Delhi and Karachi are unsafe round-the-clock, but it's just an example.) Since multiple inheritance is bad (it makes the source more complicated) C# does not provide such a pattern directly. But sometimes it would be helpful to have this ability. For instance I'm able to implement the missing multiple inheritance pattern using interfaces and three classes like that: public interface IFirst { void FirstMethod(); } public interface ISecond { void SecondMethod(); }  public class First:IFirst  {      public void FirstMethod() { Console.WriteLine(&quot;First&quot;); }  }  public class Second:ISecond  {      public void SecondMethod() { Console.WriteLine(&quot;Second&quot;); }  }  public class FirstAndSecond: IFirst, ISecond {     First first = new First();     Second second = new Second();     public void FirstMethod() { first.FirstMethod(); }     public void SecondMethod() { second.SecondMethod(); } }  Every time I add a method to one of the interfaces I need to change the class FirstAndSecond as well. Is there a way to inject multiple existing classes into one new class like it is possible in C++? Maybe there is a solution using some kind of code generation? Or it may look like this (imaginary c# syntax): public class FirstAndSecond: IFirst from First, ISecond from Second { }  So that there won't be a need to update the class FirstAndSecond when I modify one of the interfaces.  EDIT Maybe it would be better to consider a practical example: You have an existing class (e.g. a text based TCP client based on ITextTcpClient) which you do already use at different locations inside your project.  Now you feel the need to create a component of your class to be easy accessible for windows forms developers. As far as I know you currently have two ways to do this:  Write a new class that is inherited from components and implements the interface of the TextTcpClient class using an instance of the class itself as shown with FirstAndSecond.  Write a new class that inherits from TextTcpClient and somehow implements IComponent (haven't actually tried this yet).   In both cases you need to do work per method and not per class. Since you know that we will need all the methods of TextTcpClient and Component it would be the easiest solution to just combine those two into one class. To avoid conflicts this may be done by code generation where the result could be altered afterwards but typing this by hand is a pure pain in the ass. How to retain HTML5 Attributes on Markup I have a page with certain html markup and element attributes as shown in the snippit below:  &lt;ul class="accordion" data-accordion=""&gt;  When I edit the page as a user with the WP Administrator Role the &lt;ul&gt; remains intact upon page update. Perfect.  Yet when a user with WP Editor Role edits the page, the ul tag saves as follows:  &lt;ul class="accordion"&gt;  Notice the data-accordion attribute is removed.  How can I get WordPress to retain markup tag attributes for users with the Editor role? Comparing signatures of apks I have two .apk files that are supposed to be different versions of the same app. What is the best way to check if they where both signed with the same key?  I want to make sure no mistakes were done and the newer version would be treated as an update of the same app. Can I recover app data after the phone has been Factory Reset? Without remembering application data, I reset my Galaxy S3 to factory state. Now, I lost data for one expense manager app. Is there any way to recover the data? When should comments be flagged/deleted on per-site metas? We all know , but that guidance is, naturally, geared toward main sites, where we want to keep things clean and focused.  Meta, on the other hand, is a site's "second place", with some different rules and conventions.  For example, questions on main sites can be closed as primarily-opinion-based, but meta is all about opinions.  There's a "discussion" tag and such questions collect many opinions.  Meta is different.  Occasionally I see comment flags on metas and I'm never sure what to do with them.  Setting aside things that are blatantly offensive or spam (that's a no-brainer), is there such a thing as "too chatty" or a comment discussion that should be moved to chat on meta?  I am very conservative in deleting things on per-site metas (except on  posts, which like main should stay focused).  Are there any guidelines specific to per-site metas?  I'm specifying per-site metas and not MSE because MSE seems to have conventions that fall somewhere between "main site" and "per-site meta".  If the answer is the same for all metas then great, but I don't want to assume it'll be the same. Why do shadows from the sun join each other when near enough? I was laying on my bed, reading a book when the sun shone through the windows on my left. I happened to look at the wall on my right and noticed this very strange effect. The shadow of my elbow, when near the pages of the book, joined up with the shadow of the book even though I wasn't physically touching it.   I have posted :The video seems to be the wrong way up, but you still get the idea of what is happening.  What is causing this? Some sort of optical illusion where the light gets bent?  Coincidentally, I have been wondering about a similar effect recently where if you focus your eye on a nearby object, say, your finger, objects behind it in the distance seem to get curved/distorted around the edge of your finger. It seems awfully related...  EDIT: I could see the bulge with my bare eyes to the same extent as in the video! The room was well light and the wall was indeed quite bright. Can I travel to the USA while working remotely for my non-US employer?