# Classical Physics

- Principles developed before the rise of relativity and quantum mechanics. Mechanics, Electrodynamics, Thermodynamics, Optics...
 Meta Thread / Thread Starter Last Post Replies Views Views: 68,419 Announcement: Follow us on social media and spread the word about PF! Jan16-12 Before posting anything, please review the Physics Forums Global Guidelines. Again, for some odd reason, people... Apr22-11 05:26 AM ZapperZ 1 45,388 I have always known that weight is the force of gravity. Yet I have always been confused about one thing. If you hold... Feb18-14 10:48 PM StefanT 2 296 Hello! I am wondering what supplies the energy necessary for the compression of a gas that is entrained in a flow... Feb18-14 07:41 PM crador 4 274 Hello I have a few fundamental questions about evaporation 1. In Cengel's Heat and Mass Transfer, in all sample... Feb18-14 07:37 PM Chestermiller 24 853 I'm trying to evaluate floor heating systems for installation in my new studio, and I have to admit that my... Feb18-14 02:24 PM meeotch1 3 252 For instance in an elastic collision of two indivisible particles... Why does m v^{2} stay constant? Why not m... Feb18-14 01:52 PM voko 34 1,344 My professor (for some weird reasons) makes us write "system " whenever we are asked to solve a physics problem for... Feb18-14 11:12 AM Simon Bridge 1 296 This is about a famous thought experiment, cited by Einstein at the beginning of his first 1905 paper on SR, and... Feb18-14 05:30 AM vanhees71 11 416 Hey guys, I am trying to create a 2d simulation of the earth going around the sun. However I am facing an issue. I... Feb18-14 04:35 AM BvU 3 265 The 2nd law of thermodynamics state that entropy increases with time and entropy is just a measure of how hard it is... Feb17-14 05:36 PM japplepie 8 345 Say, i have two concentric shells,each carrying a different charge.If i connect an ideal, resistance less wire between... Feb17-14 04:27 PM Nugatory 10 398 I've been having a problem with the sign of potential. Electric potential as I know it is defined as V =... Feb17-14 05:57 AM Philip Wood 7 302 What will be the degrees of freedom of a ''Connected pair of compasses''? Feb17-14 12:45 AM AbhiFromXtraZ 6 252 Would a particle kept in the path of an electromagnetic wave experience a force? Both magnetic and electric field are... Feb16-14 10:47 PM nasu 5 238 why should we use a convex lens to focus the rays at the point on the screen.why is at an angle instead of being... Feb16-14 04:39 PM Philip Wood 8 293 why do the atoms in excited state alone could emit line spectra?can't they emit when they are not in gaseous state? ... Feb16-14 04:16 PM Drakkith 1 278 Suppose you have a sphere (sphere A) with net positive charge 2Q. A conducting spherical shell (sphere B) of inner... Feb16-14 02:39 PM VishalChauhan 2 223 Hi! I just wonder what's the actual use for p=nkT≈nE_k when it comes to plasma physics? What does p help us... Feb16-14 12:05 PM rogerk8 6 318 The total energy of the magnetic field in the matter is \frac{\mu H^2}{2} , I want to calculated the energy that is... Feb16-14 11:33 AM DrZoidberg 3 290 I am studying Laplace's equation in my electrodynamics course (using griffiths intro to electrodynamics). I am... Feb16-14 10:56 AM dauto 3 239 From what I understand, an atom generates an electromagnetic field which exerts energy on objects and this... Feb16-14 10:42 AM mal4mac 2 222 So, I asked myself the question, "why does the earths force of gravity effect us so dramatically on the surface of the... Feb16-14 04:05 AM kindlin 3 220 The standard equation for the damped angular frequency of a normal damped mass-spring system is ω_{d} =... Feb16-14 04:03 AM kindlin 5 361 To preface my question, I know it is related to the Gibbs paradox, but I've read the wikipedia page on it and am still... Feb16-14 01:08 AM jartsa 1 200 Hello, I was wondering, do the Lee/Kesler correlations apply at the saturation line for vapor/liquid equilibrium? I... Feb15-14 10:43 PM Maylis 0 201 So Rayleigh scattering says that higher wavelengths of light are scattered more than lower ones - but why don't we... Feb15-14 01:44 PM Jbeats245 2 234 In kinetic theory a liquid is viewed as an incompressible substance in which the atoms are free to move. I would like... Feb15-14 01:12 PM CWatters 1 233 Hi, this is my first post on this forum, although ive often refered to many posts for random information, so thanks to... Feb15-14 12:05 PM Giorgows 6 292 Hi Is this formula all i need for finding the speed i need to tip the trolley?... Feb15-14 08:55 AM MatsNorway 26 564 Suppose we have a infinite current sheet of surface density \sigma and apply Ampere’s law to find the magnetic field.... Feb15-14 08:03 AM DaleSpam 1 181 Hello - I'm having a difficult time finding this answer anywhere else on Physics Forums. I'm curious if anyone knows,... Feb14-14 03:48 PM sophiecentaur 6 290 One question. In the text http://locomat.loria.fr/napier/napier1619construction.pdf author calculate ... Feb14-14 11:23 AM LagrangeEuler 2 298 I read that for a rotating body the kinetic energy ##E_k = \sum \frac{1}{2}mv^2 = \frac{1}{2}{\omega}^2∑mr^2 =... Feb14-14 07:47 AM A.T. 3 189 Searching through Wikipedia (http://en.wikipedia.org/wiki/File:Resonance.PNG), I found this graph about resonance. I... Feb14-14 03:05 AM maajdl 1 161 For a damped mechanical oscillator, the energy of the system is given by E = \frac{1}{2}m \dot{x}^2 + \frac{1}{2}k... Feb13-14 10:09 PM MuIotaTau 2 276 Hi all I was just wondering if anyone could help me with estimating error caused by misalignment of an optical... Feb13-14 08:23 PM Andy Resnick 2 198 I am reviewing the first chapter of my classical mechanics book (Fetter & Walecka), and in the very first section he... Feb13-14 04:09 PM mpresic 6 385 I'm having trouble understanding the idea of escape velocity. How can an object escape the gravity of a massive object... Feb13-14 03:54 PM mpresic 22 761 I've read that if you want light to diffract through a single slit, the slit opening must be equal too or less than... Feb13-14 11:24 AM Saado 3 225 I'm trying to build up some intuition with Gauss's law, calculating the flux through surfaces given certain charge... Feb13-14 09:44 AM jfizzix 2 307 Why entropy is highest at lowest energy? Entropy is disorderness.So low energy means low disorderness.But why it is... Feb12-14 08:28 PM BvU 16 433