How come in free fall you feel weightless even though gravity is pulling down on you? (ignore air resistance when answering this question).
Well, this question has been puzzling me for kinda long time, many people believe that orbiting astronauts feel weightless because they are "beyond the pull of Earth's gravity"...How far from the Earth would a spacecraft have to travel to be truly beyond the Earth's gravitational influence? If a spacecraft were really unaffected by Earth's gravity would it remain n orbit? If so, what is the real reason for weightlessness in orbit?
Unreasonable RAM usage in Windows 7 I have a fresh install of Windows 7, and my RAM in normal startup goes up to 2.5GB. I looked at Task Manager, and there's at least 1.5GB missing from there and in Resource Monitor as well. There's no indication of what's using that RAM. Can someone tell me how I can find out what's consuming my memory? I believe it's a virus, but none of the free antivirus programs tracked it down.   I added the pictures below. If this is normal usage of Windows 7 as some answers imply, then I don't get this at all.   P.S. My Windows 8 Installation was running below 2.5GB, actually it was 1. something, until recently that I transferred some files from another computer which had the same problem that mine has now. I deleted Windows 8 and installed Windows 7, since I would do that anyway, and now I'm getting high memory usage in Windows 7 as well.   (Click images to enlarge) Series convergence or divergence how to test I have the following series defined.   $$\displaystyle\sum_{k=1}^{n} \cos \left( {\frac{\pi}{2}} k \right) \frac{k}{k+1000} \frac{1}{\sqrt{k}}$$ where $n = 1,2...$  How to test whether this series converges or diverges ? "Insufficient storage" when trying to install new app Every time I go to install a new app, I get the message "Insufficient storage", and an unable to install anything!  I am using Samsung GT19060 my internal memory is 8GB. I have not downloaded anything but anytime I try to download something it will tell me low memory space. How do I remotely control another Ubuntu desktop from Ubuntu? How do I remotely control another desktop (both are Ubuntu 12.04) from my client machine?  Is it possible to use Remmina Remote Desktop Client? Changing content of footline in beamer How is it possible to set a specific text in the footline of the slides in beamer? In my case, author names and the title are shown. Instead I'd like to show the conference name and country.  \documentclass{beamer} \usetheme{CambridgeUS}  \author{Elena Piper, Amina Shahid, April Fiorese} \title{Evaluating the Change of Performance Metrics for Key ABS}  \begin{document} \maketitle  \end{document} What does // mean in a path? When a land becomes creature, can you kill it? Show that the Euler characteristic of a chain complex is equal to the Euler characteristic of its homology I have an issue which I've been struggling with today. The JSON is returned back to me with a project Id as the key, this Project Id is dynamically generated and due to this I have not been able to come up with a way to deserialize this response. Any suggestions?   {      "success":true,    "numRows":5,    "data":{         "23000079":{            "projectId":"23000079",          "name":"Mcdonalds",          "departmentId":"9383",          "responsibleUserId":"7444434"       }    } } What are the regional Pokémon? I have heard that there are some Pokémon that are region specific.  Could someone please clarify which Pokémon are region specific and in which regions that they can be found in? What is the cause of this sudden drop in CV queue size? At Sat, 30 Nov 2013 14:51:01 GMT, there was a sudden drop in the close votes review queue size from 98932 to 98314. This is about 600 questions over the course of one minute.  It doesn't seem like a routine cleanup script. If it was, this is a very odd time for it to run. Also, the drop occurred over the span of a minute, so it's highly unlikely there was simply increased review activity. So, I ask: What was its cause?         (yes please don't shoot me I know my freehand circle is blue) (it's actually a dark teal look again) (the source for this script I  (slightly modified), found through  post)  Raw data:  Epoch time  CV Size 1385822821  98932 1385822881  98932 1385822941  98932 1385823001  98932 *** 1385823061  98932 *** 1385823121  98314     [author's note: the difference between iterations is 60 seconds] 1385823181  98314 1385823241  98314 1385823301  98314 1385823361  98314 When I create a UV sphere and add the subdivision surface modifier, the following wrinkle appears.    How can I avoid it?  I've read the article  but there seems to be no clear solution.  UPDATE 1  I've used the word 'apply' in the first sentence of the initial version of this question. It's misleading since I want to preserve the modifier without 'applying' it. Rather, what I meant is 'adding' the modifier.  UPDATE 2  I followed josh sanfelici's solution, but still there is an artifact at the pole.  Here is the screen: (A rendered view with a sun lamp)    Maybe it's the limitation of the general-purpose subdivision modifier.  BTW, when the cast modifier is added after the subdivision modifier, the sphere becomes perfect (even for my original wrinkled sphere).  But since I want to edit the resulting sphere (for example, scaling X, Y, etc) while modifier is added but not applied, it's not usable. Let $ \sigma(A)$ be the set of all eigenvalues of $A$. Show that $ \sigma(A) = \sigma\left(A^T\right)$ where $A^T$ is the transpose matrix of $A$. How do you use Batch for send more than 10 emails? Why does cancellation of dots $\frac{\partial \dot{\mathbf{r}}_i}{\partial \dot{q}_j} = \frac{\partial \mathbf{r}_i}{\partial q_j}$ work? I uploaded a pre-print of an article on arXiv 1 year ago. The article was accepted in SCI journal and currently available online. However, I found a typo mistake in one equation and want to add more discussion related one figure (On researchgate I am receiving a lot of queries regarding that figure). Should i upload a new version of pre-print on arXiv? (How citations will work in this case? as arxiv version is more advanced compare to Journal version) OrI may upload a short document on arXiv as an errata/correction with extra discussion?Or I may address errata and discussion in online page of journal? Actually this journal allows the registered users to comment and start discussion related to published article. Difference between force.com and salesforce.com? What the difference between the two?  This description seems to be a bit out of date and underspecified. If I add a comment but navigate (by mistake) to another page, I lose my unfinished comment (ok, depends on browser etc). On the other hand, when formulating a question, and I click on a link by mistake, I'm asked if I really want to leave.  It would be nice to have this warning for comments as well. The 'nofollow' attribute is set in user profile website link... why? I understand that from an SEO perspective it is beneficial for Stack Overflow to have the  on the website link for user profiles. Especially if people will just create an account to get a backlink. What I think however, is that contributing members of Stack Overflow should be awarded with this backlink. I think that if someone contributes and has some decent reputation, then they should not have nofollow set on their website link in their user profile. Considering the amount of users that are backlinking to Stack Overflow with flair, I really think that Stack Overflow should hook us up with some search engine love. Why would Littlefinger want this person dead?