I'm a retired police officer trying to learn classical mechanics on my own. I have gone through many links on the Internet including the classical mechanics quick reference textbooks from Physics Stack Exchange. But, I always have the same problem just as anyone trying to learn classical mechanics on his/her own has had the experience of "going down the Classical Mechanics Rabbit Hole".     It turns out that only classical mechanics is the most difficult part of physics to learn on ones own. I had a friend who confirmed this by comparing how difficult it is to learn classical mechanics (including Lagrangian and Hamiltonian formulation) on his own with electrodynamics and general relativity. (Who are much much more difficult that all the field of CM)   For example, suppose you come across the novel term vector space, and want to learn more about it. You look up various definitions, and they all refer to something called a field. So now you're off to learn what a field is, but it's the same story all over again: all the definitions you find refer to something called a group. Off to learn about what a group is. Ad infinitum. That's what I'm calling here "to go down the Math Rabbit Hole."  For example, I had lot of difficulties with the book "An Introduction to Mechanics" by Daniel Kleppner, Robert J. Kolenkow, which seemed according to many views to be an easy approach toward Newtonian and relativistic mechanics. The authors in general only and quickly pushes equations in my front without giving any reason for why a certain procedure is correct, and give no explanation on most of the things. I had then one choice: search on the net. But when I do, to search for a term X, I get to wikipedia page X, who give a definition that contains another term Y, where I click to understand the full meaning of term X, but who then contain another term Z, who redirects to... which leaves me with no understanding.  Another thing is that when I go here on Physics Stack Exchange, and when I see answers like:        and many many others... (like an answer by David Z for a question that kinda looks like: 'Would a heavier object fall faster because they attract earth stronger', I have no idea where he found the equations he wrote down. Also in many applied physics questions and answers by Lubos Motl. And in some questions: like: 'Why Newton's third law apply to all inertial frame?' I have no idea about that even if I already learn a lot from Daniel's book.)   I don't know where those guys got all that stuff. I feel like: Mechanics is not well organized. For example, in relativity we first learn about Galilean relativity, then special relativity then general relativity. Everything is in order and it makes  of the understanding a lot smoother. (according to my friend) But in classical mechanics I don't know where to start  or what to pick.  In Lagrangian and Hamiltonian mechanics book, it is even worse.  Result? I fail to correctly answer some basic questions like: what happens when a cup of water starts to melt? or even more easy physics questions.  So I'm searching for a clear textbook that explains Newtonian mechanics well, then goes to special relativity, then to Lagrangian and Hamiltonian mechanics.  My dream for the next years of my life is to understand mechanics: Newtonian, SR, Lagrangian and Hamiltonian. And to start writing a web page about explanations of different phenomena like John Baez this week on mathematical physics. And maybe to do research on problems in classical physics which would make of me the most happy man in the world.  Regards. Thanks for your understanding and time. My situation is similar to   My background: I'm very old, so I forgot almost all the math/physics I've got in school, however, I've taken courses on Algebra, trigonometry and single variable calculus using KhanAcademy and some MIT videos. I've taken an MIT test on CalcI (just downloading the test online and verifying the solutions) and I scored 90%.
What are some good books for learning the concepts of Kinematics, Newton laws, 2D Motion of Object etc.?
What does increased caster level affect? A  adds +1 caster level, what does this affect?   Damage from spells? (Like fireball) Duration and area of effect? "Amount" of effect (Like number of missiles from magic missile) Spells known by a wizard (ie +1 caster level mean a level 2 wizard gets the spells as if they were level 3?) Anything else? Get Edge / Vertex / Face from mouse position Record Animation In BGE minitoc package adds extra page when used with float and lastpage packages The minitoc package adds extra page when used with float and lastpage packages. I figured out that this problem can be resolved by loading minitoc package before float and lastpage packages. In LyX the float package is loaded automatically and could not figure out how to force LyX  use minitoc package before loading float and lastpage packages. Thanks in advance for your help.  \documentclass[a4paper,12pt]{book} \usepackage[english]{babel} \usepackage{blindtext} \usepackage{lastpage} \usepackage{fancyhdr} \usepackage{float} \usepackage{minitoc} \begin{document} \dominitoc \tableofcontents \mainmatter \chapter{First Chapter} \minitoc \section{Introduction} \blindtext[1] \section{Material \&amp; Method} \blindmathpaper \chapter{Second Chapter} \minitoc \section{Introduction} \blindtext[1] \section{Material \&amp; Method} \blindmathpaper \end{document}   Edited  It is also working in LyX 2.1.1 if I remove \includepdf[pages={1},scale=1]{Back.pdf} at the end of the document. However if I include \includepdf[pages={1},scale=1]{Back.pdf} at the end of the document it adds extra page. Any thoughts.   Updated  I've narrow downed the problem. My following MWE in .Rnw format adds extra page at the end of document when using minitoc package. Thanks again for your help.  \documentclass[a4paper,12pt]{book} \usepackage{minitoc} \usepackage[english]{babel} \usepackage{blindtext} \usepackage{lastpage} \usepackage{fancyhdr} \usepackage{float} \usepackage{pdfpages} \begin{document} \dominitoc \tableofcontents \mainmatter  \chapter{First Chapter} \minitoc \section{Introduction} &lt;&lt; Test &gt;&gt;= 1:50 @  \blindtext[1] \section{Material \&amp; Method} \blindmathpaper \includepdf[pages={1},scale=1]{Back.pdf} \end{document} I have a script that needs to do some stuff based on file creation &amp; modification dates but has to run on Linux &amp; Windows.  What's the best cross-platform way to get file creation &amp; modification date/times in Python? Django - specify which model manager Django admin should use How is hotness score calculated at larger sites? To start with, I am aware that hot questions from larger sites are somehow "penalized" and :     This is designed to ensure that a single site doesn't dominate the list, and that users see a good sampling of questions that are likely to interest them throughout the network...   I would like to understand how is hotness score really calculated at these sites. The reason why I ask is that per my observations, this seems to be quite different than is documented in the . Specifically, I would like to understand the difference in the impact of answer(s) score and aging factor.  Regarding impact of answers score, my observations of hot questions from smaller sites appear to be in agreement with known formula: (MIN(AnswerCount, 10) * QScore) / 5 + AnswerScore. For example, a question with low score (+1, +2) can get into hot list if it has got answer(s) with sufficiently high score.  At larger sites, this doesn't seem to be the case. Say, it looks like Stack Overflow questions just don't enter hot list until they reach certain score (+6,+7), no matter how many answers are there and how high is their score.  Does system simply totally ignore answers until question reaches certain score?  Another thing I noticed is that questions seem to age away from the hot list 2-3 times faster than ones from smaller sites (having comparable question and answers scores). Granted, this is harder to track and I am not yet sure if I figured that correctly. Do larger sites questions age away faster than those from smaller sites?    For those interested, here is a (partial) list of example questions I studied before asking this: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , .  Although above examples are only from Stack Overflow, my question isn't (I only used it as an example of a large site in my studies). I would like to understand if hot questions from other larger sites are handled in a similar way. I have the following code for my masterpage:  &lt;%@ Master Language="C#" AutoEventWireup="true" CodeFile="MasterPage.master.cs" Inherits="MasterPage" %&gt; &lt;?xml version="1.0" encoding="UTF-8"?&gt; &lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"&gt;  &lt;html xmlns="http://www.w3.org/1999/xhtml"&gt; &lt;head runat="server" style="position:relative"&gt;     &lt;title&gt;Masterpage&lt;/title&gt;     &lt;asp:ContentPlaceHolder id="head" runat="server"&gt;     &lt;/asp:ContentPlaceHolder&gt; &lt;/head&gt; &lt;body&gt;     &lt;form id="main" runat="server" style="position:relative"&gt;     &lt;div&gt;         &lt;asp:ContentPlaceHolder id="MainContent" runat="server"&gt;         &lt;/asp:ContentPlaceHolder&gt;     &lt;/div&gt;     &lt;/form&gt;     &lt;br style="clear:both" /&gt;     &lt;form id="footer" style="position:relative"&gt;     &lt;div&gt;         &lt;center style="font-size:small"&gt;Footer content&lt;/center&gt;     &lt;/div&gt;         &lt;/form&gt; &lt;/body&gt; &lt;/html&gt;   My problem is that when the MainContent isn't filling up the page the footer is not at the bottom of the page. Is there a way to force the footer to stay on the bottom of the page if the main content isn't pushing it all the way down? When the main content is "big" enough it pushes the footer down with the content and displays on the bottom when scrolling down, but not if it is to small.  Anybody know how to fix this? Cubic polynomial with three (distinct) irrational roots I am looking for an equation     $$x^3+ax^2+bx+c=0, \qquad a, b, c \in \Bbb Z,$$   of degree $3$ that has $3$ different roots.  For an equation of degree $2$ it is easy---for example $x^2-2=0$---but I can't find an example for degree $3$.  if there is a method for finding this kind of Equation I will be grateful. Comprehensive list of activation functions in neural networks with pros/cons Are there any reference document(s) that give a comprehensive list of activation functions in neural networks along with their pros/cons (and ideally some pointers to publications where they were successful or not so successful)? It always takes a  and money to find the next . Why is it so important to do this work and what is the application those numbers? Why are some of my screen-recording/capturing/sharing applications (or app features) not working in Ubuntu 17.10 (and later releases)? After upgrading to Ubuntu 17.10 I noticed some of my screencasting applications are not working, for example screencasting tools like SimpleScreenRecorder and vokoscreen. ()  Also I noticed features like screenshot from GIMP is not working properly, producing blank screenshots (). Shutter too is producing glitchy screenshots ().  Screen-sharing option on Skype is also not working ().  The issue occurs sometimes on later Ubuntu releases too.  Why is this happening and how do I fix this? What happens when a field turns on or off? Short Setup  I am curious about the the mechanics of fields, whether , , etc.  So as a specific example in order to simplify (hopefully) how to ask this question, consider  or , specifically interactions between .  My specific curiosity is in how we handle the "sudden" creation or loss of a source and how the source then creates its associated field.  My naive guess is that the loss of a source (e.g., annihilation) might be easier to handle, but let's focus on creation of a source for now.  Questions  The specific example of pair production interested me because I was wondering:   How does the field arise from the sources?   Meaning, is it delayed until after the source  fully "condenses" from the , for instance? Or does the field slowly "turn on" as the source "condenses"?   Perhaps I should have asked whether it we know if it takes time for sources to form (I assume it does).  If so, can we describe this from first principles or is it empirically based?  Am I asking that in a very uncomfortable manner?  If so, I would appreciate any suggestions.  For instance, is there a better word than "condense"?  I was thinking about water condensation as a very loose analogy to the purpose of the Higgs field in the formation of massive objects.  Why can they be produced without immediately recombining?   That is, how "close" are the two sources spatially after formation and what energies are needed to overcome the associated potential?  Does the field emanate/propagate as if from a point source?   I ask because I am trying to determine whether this is a simple  issue (i.e., far away it's just like a point source) or if the field emanates only from the "surface" of the source (e.g., ). If it starts from "within" the source as the source forms, do we know how to handle this mathematically?   My concern arises from the "similar" problem of bubble formation, where the bubble starts with zero radius which would require an infinite energy.  Perhaps the analogy is not appropriate?     Purpose  I ask these questions because it struck me this morning, while driving to work, that I did not know how and when a field "turned on."  I started to think about pair production and then quickly became confused (not difficult to do) and thought many of the quantum whisperers on this site would be much better at explaining these nuances than any of my failed rummaging through Wikipedia or scholarly articles and old text books. I am having a problem with Windows 7. When I boot up, the CPU jumps to 100% execution for about 10-15 minutes. During this time, it is really slow, and if I play any music, the songs play slowly and sound distorted.  I tried to scan my computer with different antivirus programs, I used Spybot, HijackThis, and CCleaner, but I didn’t find anything of note.  I watched the process list in Task Manager and saw that there are two processes that are to blame. There are two copies of svchost.exe, one using ~48% CPU, the second (under the Network Service account) using ~37%. For the first 15 minutes, the CPU runs at about 70-80%, then eventually drops to 30-40%.  I don’t know what to do. I could not find a way to stop the services, and if I try to kill them, sometimes the system crashes. In my native language, double negations "cancel out". I have been trying to learn English using movies and such things, but double negation confuses me. I see instances when double negation cancels out, and some when they do not.  For example, "I haven't got no money" is interpreted as "I have no money." "There wasn't anyone who didn't enjoy the party" is interpreted as "Everyone enjoyed the party."  Is this context dependent? If so, how does one decide which interpretation is correct? How do I prove or disprove $X \times (Y \cup Z)= (X \times Y) \cup(X\times Z)$  for all sets $X$, $Y$, and $Z$? I'm lost on the steps here. Prove: $\binom{n}{0}F_0+\binom{n}{1}F_1+\binom{n}{2}F_2+\cdots+\binom{n}{n}F_n=F_{2n}$;  I was stuck with this question for a while... Help me please!!! Thanks!!! What is the best way to modify a list in a 'foreach' loop? I'm building a small chat. Now I see but in other chats (whatsapp, facebook mobile chat, sms ...) that the arrangement is always the same:  Left: the chat partner. right: myself      Why is that? Transparent model when exporting fbx file to Unity So I have this shark model which I animated and ready to export it on fbx and transport it to Unity.  But When I put it on Unity, It looks transparent like this.    Many of the solutions online say that the problem is because of my faces, and they told me to recalculate it or something, but normals are just fine. Is there any other solution?  here's the blend file: