Classical Physics

If 2 identicle particles are travelling in the opposite direction just after the big bang, will they be opposites of each other? eg. particle/antiparticle

The article proves that MM experiment has nothing to do with checking the Newton's view on absolute space and time. To analize whether light spreads relatively to the moving source of light with relative speed one can reconstruct the experiment and redo it. http://www.rainbow-calendar.hotmail.ru/Michelson and Morley.htm Though it is quite possible that light spreads relatively to the moving source of light with absolute speed, but nevertheless it is useful to check it. As I see it, the concept of "the ether wind" is not the "Newton's wind", that is the shift of light due to the movement of the source to the direction, from which this source moves. An the MM experime…

1. It is really neat how the Lagrangian Equations of Motion can be derived from Hamilton's Variational Principle, and solve so many classical systems much easier than from a Newtonian approach. Does anybody have any leads to how Lagrange came up with his "Lagrangian", specifically the equation: [math]L = T - U[/math] where T is the kinetic energy and U is the potential The equation seems somewhat arbitrary and made up yet it works! 2. The second question is, who really came up with this formalism? The Lagrange equations are derived from Hamilton's principle (or can they somehow be derived from each other?), but then again, Hamilton's principle has the Lagran…

Hi. Which drag coefficient is greater; a rounded leading edge or a razor sharp leading edge for a given wing/keel ?

what exactly makes a chamber resonate with a particular frequency? especially in relation to electromagnetic waves.

nevermind...I figured out my question.

Hi. What is the force exerted on a 1m² vertical plate held transversal submerged in a river flowing laminar at 0.5m/s ?

Anyone fancy deriving the formula: Q/t = (1000 W/m^2)eAcos(theta) where (1000 W/m^2) is the amount of energy striking the surface of the earth at right angles per second per square metre, "e" is emissivity, "A" is the area of the entity and "theta" is the angle of incident light -------- ignore the following if you don't care why i'm curious! (I'm using it specifically to show a proportionality between energy absorbed [Q] and cos(theta) so that i can show that since q=It and E=kq/r^2 so substituting (q=It) E=k(It)/r^2 therefore current is proportional to energy, indicating the fact that if a higher current is produced, more energy is involved…

I am looking for liquids or substances that turn black when heated. I know anything can be burned, but i want something that would turn black on a controlled bases. or perhaps something that would turn black due to the reaction of positve or negative charges?

This will be the first of a few threads which will lay the groundwork for a discussion of Newtonian gravity theory old and new. I am splitting the concepts into threads so that each thread can stand alone as a good introduction and reference for the mainstream scientific position. Here we will limit discussion to known and accepted scientific knowledge, and I will present everything at a high-school level so that virtually anyone can understand the concepts with a little effort. I will also refrain from straying from the status quo without the support of clear mathematical proofs or simple thought experiments that are uncontroversial. Finally, for this thread I …

hey i need help with a question, i need to be taught. So if you would please aswer this question for me and also tell me how you got that answer, that'd be great! a girl, standing on the roof of a house which is 5m high, throws a stone vertically upward. It strikes the ground 7s after being thrown. calculate: a) the initial velocity b) the maximum height the stone reaches (abouve the ground) c) the velocity of the stone as it strikes the ground

I was on a game forum and someone raised the issue that Newtons law of gravity is not a law anymore because of "Minkowski's Space". I said it was still a law and when I googled it everywhere I still see Newtons law of gravity as still a law. Is it still? Bettina

I'm writing to you now to spread the word about some inventions i've been working on. I don't know if they will work, but the ideas are better off in the hands of more than one person. I'm not asking for assistance, simply sharing the ideas. I do hope someone experiments further with the ideas or spreads them to someone who will. On to the inventions. All of the inventions/ideas serve more or less the same purpose and they revolve around the use of magnets. The purpose is energy. I've come up with a few designs which might work to generate electricity, produce mechanical energy, and improve certain kinds of energy efficiency. Idea #1: This one is mainly for impr…

Hey everyone, I'm getting ready to start my IB Extended Essay in Physics, and sent a proposal to my supervisor for a study on the performance of various solid rocket engines. Unfortunately this topic was rejected because a) it involves highly explosive and flamable materials, b) apparently I need more advanced lab equipment and c) it is more like a chemistry topic. So now I have a HUGE problem. I am supposed to have a topic and introduction and outline finished, and I don't even have a topic! I was wondering if anyone here had any ideas for a physics topic that provides a problem which I would then come up with a hypothesis for, and then prove through experim…

I've been wondering for quite some time how double-parabolic mirrors (such as the ones for sale here and here[yes, same product, different pages]) work. Specifically, I'd like to know the issues behind image coherency and the focal points of the mirrors. Thanks in advance.

Wow - I love this place - just spent about an hour reading through the forums. Anyway - my question relates to this: (cue violins) Basically - someone was driving too quickly and went in to me as I pulled out. There is no way I could have seen him - but of course it's probably going to be considered my fault Now, I used this peice of literature: http://www.harristechnical.com/articles/skidmarks.pdf to make this: http://www.mintylamb.co.uk/crashomatic.php 14 metres of skidmarks means he was doing around 30mph - which is on the limit - and certainly too quick for the residential street. HOWEVER - one big factor (I think) is the fact h…

I would like to know what scientists are searching for, and what about like gravity....i know its a force, but besides that why does it propegate..and why isn't there anything faster than light...since it's a wave...and sound is also..why wouldn't it make sence that there is a faster type of wave?

In the famous equation, how is c the velocity of light expressed? How do you express velocity, without a refrence to distance or time?

How much centrifugal force is created by the Earth's rotation, if any? It is obviously not enough to counteract the Earth's gravity, and send us all flying into space, but is there still some acting on the bodies on the Earth?

And I realized that the cue ball wasn't doing what I thought physics said it should. So obviously I have the physics wrong. I know that if you hit the ball slightly to the left of the center produces a spin on the ball. As you look at the ball from the point where you hit it, it spins from right to left. Now, this should make the ball go to the right of the straight line of where it's hit, right? But, it keeps going left, hits the side and then produces this weird drag on the ball. I guess I don't understand the physics of side spin on a pool ball. Can someone enlighten me?

....through the middle of the earth, and you jumped into it, what would happen? once you fall into the center of the earth there is equal mass, or almost equal mass maybe theres a mountain on a side, on each side of you. so i think they either cancel eachother out, our there is equal force to every part of your body. or maybe you'd fall out the other side. so what do you guys think would happen? or know what'd happen.

well heres a small problem, do you think i have a reasonable esimate/answer ? Cheers -Sarah

Repost from the general thread. For some reason I didn't see the Physics or Math sections the first time I logged in, my apologizes. I was reading The Fabric of the Cosmos (okay, listening to the book-on-tape during my drive home...) by Briane Greene. He was explaining how Newton thought about space and absolute-space and brought up Mach's (I believe it was Mach anyway) example about being in a void. Nothing around just a black void, and then you started spinning. Newton explained that once you started spinning your hands would want to move away from your body. Mach didn't think that would be the case, to him it was because if there wasn't anything in spac…

Hey Everyone, I'm new to the forums - and have spent the last day reading threads that seemed to be in another language. I'm heading to college for my freshmen year in about 3 weeks to major in Mechanical and Biomedical engineering. I've been extremeley interested in science in school - but have not had the time to pursue it in my free time. Now that I'm finished with my job and have some free time to lounge around and read whatever I want, I'm looking into reading science and math related work. I really enjoy the stuff, but have immersed myself in classical literature for the past few years. Basically, the point of this thread is for me to ask you who are more expe…

I was just wondering if it was possible to actually create these so called Mag-Lev vehicles and have them behave the way they did in the movie. I know they have been working on monorails and even a magnetic propulsion device that has the capactiy to launch rockets, saving all that costly fuel, but never any cars with this design. Also, the guns used in the scene in the car assembly line, I never figured out if it shot sound blasts or just intensified blasts of air. Thoughts on this?