# 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: 5,463 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 48,253 Forgive me if this is in the wrong category. I have a product I am working out - I am a programmer and electronic... Aug15-14 11:53 AM jedishrfu 4 182 After being through with Newton's 3rd law of action reaction pairs, there arise a doubt regarding the categorization... Aug15-14 11:35 AM swayne221b 6 190 Hi, First of all, this is not my expertise so I'm sorry for things that are noted wrong. I would like to know some... Aug15-14 11:03 AM berkeman 5 1,405 I understand that the dynamic modulus of a material is measured by inducing a sinusoidal force and measuring the... Aug15-14 09:20 AM Chestermiller 3 208 I have a system described by the hamiltonian H in the coordinates i, p_i . A transformation of the type $Q_i =... Aug15-14 08:07 AM newton_1372 4 271 If I have particle moving in the potential ##V(x)##, when I write equation of motion ## \frac{dx}{dt}=-V'(x)+q(t)##... Aug15-14 03:23 AM Shyan 7 192 According to Fermat's Principle (modified version) a light ray takes an extremum path. Can anyone explain the physical... Aug15-14 12:25 AM Shyan 1 160 It is possible that a fixed point to be attracting but not Liapunov stable. I can't find any example of that. Aug14-14 08:56 PM beman 0 143 This is from Wikipedia: 1. What is really meant by "self-propagating", how it works? 2. How many electric... Aug14-14 06:21 PM pleco 44 971 Why do we use inertia in rotational motion and not the whole mass of an object ? Aug14-14 01:24 PM Pythagorean 3 162 Why is the weight of the liquid displaced = buoyancy force and not the weight of the submerged volume of the object? ... Aug14-14 01:19 PM shangriphysics 9 249 Consider a parallel plate capacitor with layers of dielectric between its plates somehow that the interfaces between... Aug14-14 01:17 PM Born2bwire 1 140 Hello, On p.573 of Jackson 2nd Ed. (section 12.1), he says, "From the first postulate of special relativity the... Aug14-14 11:39 AM HJ Farnsworth 2 201 Suppose I have a sealed container of fixed volume containing 3/4 air and 1/4 of some liquid by volume at room... Aug14-14 10:43 AM Larry Shick 4 239 If I understand it correct during hammerthrow an athlete muscles cause Fcentripetal force on a ball and ball cause... Aug14-14 06:31 AM rcgldr 11 225 Hi to all. I'm looking for ways heat could be converted directly to electrical energy. I figured out some machinery... Aug14-14 03:51 AM inelwk22 15 1,307 I know that if density of an object is equal to density of fluid, the object will be fully submerged hovering right... Aug13-14 07:33 AM sophiecentaur 7 209 Entropy gave us that everything can happen, just that the chances of it happening is very slim. If time is infinite,... Aug12-14 10:16 PM Simon Bridge 6 402 I have been struggling with the following; (apologies if this is a simple question) After reading the Hershel... Aug12-14 01:41 PM mfb 3 197 Hello all, as a recent graduate and a new teacher, I am living in Honduras and teaching the sciences in a high school... Aug12-14 01:06 PM Rocky9242 2 216 Quick question. If the EM field vectors are perpendicular to the direction that an EM wave is traveling, how can light... Aug12-14 12:29 PM DaleSpam 58 1,453 Hi Folks, Why does a parachutist experience 0g (assuming falling in a vacuum, no drag) when falling towards the... Aug12-14 06:11 AM Lsos 4 286 I'm trying to understand the kinematic equations well enough to explain to someone else, but the analogies I've come... Aug12-14 02:14 AM haruspex 3 205 Hi everyone, A couple of question I was thinking about regarding sound: 1) A sound source is moving at the speed... Aug11-14 07:34 PM billy_joule 6 299 I am not sure if this question even makes any sense, it just popped in my mind while reading a book on special... Aug11-14 02:50 PM Orodruin 37 864 Hi all, I've got a quick clarification question. Generally when the production of electromagnetic waves are... Aug11-14 02:34 PM DaleSpam 2 164 I don't really understand what is the need of giving feedback in the magnetostriction method to produce ultrasonic... Aug11-14 01:27 PM smart_worker 2 277 Before you go through all the trouble of reading all this back story the real information is towards the bottom... Aug11-14 08:35 AM A.T. 17 378 TIR (total internal reflection) is the most common way of producing evanescent wave, e.g. TIR fluorescence microscopy.... Aug11-14 05:34 AM iuvenes 0 222 Just wondering, in order to polarize a light beam with a wire grid you could also get some difraction in despite of... Aug10-14 08:22 PM namati 2 186 I am confused with the wording for a static friction problem; this particular wording also lead me to a conceptual... Aug10-14 09:16 AM KatamariDamacy 13 342 I'd like some help to understand how to calculate "lost work" for irreversible heat transfer across a finite... Aug10-14 02:56 AM PatrickAndrews 12 415 I've been looking into electromagnet design and there is a certain principle/set of equations that are bothering me...... Aug9-14 10:57 PM Simon Bridge 5 326 Folks, I am having difficulty correctly representing a mechanical system within a correct "control volume at an... Aug9-14 03:14 PM bugatti79 7 275 $$\vec{F}=q\vec{v}\times\vec{B}$$ $$\frac{d\vec{F}}{dq}=\vec{v}\times\vec{B}$$$\$\int\frac{d\vec{F}}{dq} \cdot... Aug9-14 12:20 PM iScience 1 234 Coming from a Chemistry background, we seem to flippantly explain away chemical phenomena using "Coulomb's Law" but... Aug9-14 05:24 AM DeltaČ 7 301 I managed to confuse myself with a simple thought experiment. I have a space ship that uses mechanical springs... Aug8-14 05:16 AM fulis 2 229 I need to do something for a project. Basically, I need to be able to project a clear image onto a mirror while still... Aug8-14 03:53 AM sophiecentaur 7 251 I am working on making an aluminum truck bed cover for a customer despite my attempts to pass it up, he insists that i... Aug7-14 06:59 PM Metal Man 30 721 What is the minimum speed at which electrons can be emitted? Why is it I never heard of really slow moving electrons,... Aug7-14 04:47 PM Nugatory 27 701