Classical Physics

How do electrons move in Alternating current ? I mean it is usually said that electrons go back and forth like on that video. But on that one the electrons flow in a sinusoidal way and they move in only 1 direction (they don't go back and forth, at least on animation). I am confused how the actual movement of electrons in AC looks like ?

Hi, I am seeking advice, direct or indirect (link to helpful resources), on transforming bending moments from local to global coordinate system using 3-D permutation tensor. For example, I have a series of bending moments acting on a node but in a local coordinate system and I want to transform these to the global coordinate system. From my reading on this the 3-D permutation tensor is used in conjunction with a function for the local bending moments and transforms them into global bending moments at that node. Global coordinate system [1 0 0 ; 0 1 0 ; 0 0 1] Local coordinate system [ 0.707 0.707 0 ; -0.707 0.707 0 ; 0 0 -1] A vector P <px, py, px> rep…

Hi I am not an Engineer or physicist this is something my idle mind came up with.. in the picture above you will see that two lever will move to container up and down when water/liquid in them is moved that will shift the gear left and right and that will rotate the gear 180 degree to start jobs ladder which will be turning the small gear which will be used to transfer the water from one bowl to another and even the weight from the lowering container can be used to do same now i was wondering that since the water container does not need to place very far vertically will the siphon law and some use of the some gear say four of it be used to do so.....

Has anyone see a Lagrangian of the following type before? If so where? Consider [math]\mathbb{R}^{2}[/math] equipped with local coordinates [math](x,y)[/math], then then Lagrangian I am interested in is of the form [math]\mathcal{L} = \dot{x}\dot{y} - y^{2}[/math] where I have set any necessary dimensional constants to 1. I won't say exactly where I have encountered Lagrangians like this quite yet, but I will later once I have finished the work. Right now I was wondering if anyone has seen something similar in any context? Technically it is of mechanical type but not what I would call standard.

Hi having a bit of a problem of late with my collection of cassettes. When I leave them, usually overnight, the section of tape that was 'exposed' has been erased. What sort of radiation could be causing this? The machine is switched off at night and sited well away from any strong magnetic fields etc, apart from which, any cassettes that have been stored partially wound, lying in my drawer, have also been similarly affected. This is becoming increasingly annoying / worrying, and is happening now on a nightly basis, so any info would be greatly appreciated. Thanks, Andrew

i have read somewhere that capillary action have limit of around 32 feet due to atmospheric pressure i may be wrong. But what if we use multiple capillary to runs small turbine like in image how viable will it be for running small light in a house

I come cross one proof the Landau-Yang Theorem, which states that a [latex]J^P=1^+[/latex] particle cannot decay into two photons, in this paper (page 4). The basic idea is, the photon's wavefunction should be symmetric under exchange, however the spin part is anti-symmetric and the space part is symmetric and therefore forbidden. I have trouble understanding the argument about the space part: Since the photons conserve linear momentum in the particle rest frame and space is isotropic, they must be emitted in spherical waves. Why the space is isotropic? Is isotropy an intrinsic property of original particle or just because the final particles are identica…

Battery + Light question: How accurately or inaccurately does a (0.97)1v berryllium wired battery, keep a light in a connection shine just as bright as a (2.97v)3v copper wired battery?

I came across a website www.lhup.edu which shows how and why many models will not work. Initially i read and left the webpage but later while thinking i thought what if we can achieve the position as mentioned in the website Buoyancy motor #1 This seems to be impossible but what if we can keep the liquid in "j" shape one in the colour image will it be able to generate electricity. reference: http://jshapeliquid.blogspot.in/ https://www.lhup.edu/~dsimanek/museum/unwork.htm#buoy1

in the image the big wheel will rotate small wheel connected to a generator the for is generated by pulley attached to shaft or small wheel fixed to big wheel and is lifted manually i am not an expert that's why i need your help. Please consider it 12 grade or high school to run an set of led bulb to light a small room for 24hrs using this gear motor what will be the weight needed

Hello. So let's say we have setup (simplified) consisting of a metal rod or cylinder, inside a long tube. Surrounding the tube are magnetic rings of varying strength. The rings are placed in order of strength starting with the weakest, finishing with the strongest. I understand that the spaces if any, between them determine the distance at which the rod is attracted to each ring, but if we insert the rod into the tube and it accelerates, creating momentum, could the rings maintain, and due to strength variations increase the speed at which the rod is travelling? The benefit of rings would be that the attraction would be evenly distributed thus the rod would levi…

Does anyone have any ideas for this project? I need a mouse trap car that will move in a circle and shoot a projectile to hit a target. I was thinking of having 2 mouse traps, one connected to the front wheel and one connected to the back wheel using the usual set up to move. And to go in a circle, I would adjust the front wheels. Then on one of the mouse traps, attach it to another string that is connected to another mousetrap that will be set off once the first mouse trap reaches a certain position.

About the Doppler effect: We know that when a vehicle passes at high speed in front of a stationary observer, the sound of the horn is high frequency when the vehicle approaches, then low frequency when the vehicle moves away. My question: what happens when, on the contrary, a moving observer passes at high speed a stationary vehicle honking? Do we get the same Doppler effect? My guess: the effect is the same ...

How did Newton discover his third law? Was it his original finding or was it a restatement of someone else's, like the first law coming from Galileo? What initiated the concept of what is now known as Newton's 3rd law?

This isn't homework, I'm reviewing physics after many years of neglect. I thought this particular problem would be simple - it isn't. 2 particles of mass m<<M fall from rest along the same straight line directly down toward gravitational source M. The particles are initially a distance [latex]2R_i[/latex] apart and their center of mass is initially a distance [latex]r_i>>R_i[/latex] from M. Therefore, just to be clear, the upper particle, particle 2, falls from an initial height of [latex]r_i+R_i[/latex], and the lower particle, particle 1, falls from an initial height of [latex]r_i-R_i[/latex], both falling straight down along the exact same straight lin…

In cyclotron particle accelerator, the dees, are they blocks? I mean is that filled inside and shaping such as a block. Or a pipe shape? Not filled inside

I remember the Speed Racer movie (love it or hate it), and although it was a financial flop, it impacted me with some artistic inspiration. Physics-wise the designs of the film's race tracks just makes sense for it's jet-propelled cars. It's like driving on a giant HotWheels track. But would such a motor sport be possible in real life? We already have the technology, but I've never seen racing jet cars on a roller coaster-esque track in real life.

I recently read that the speed of light through glass slows down slightly due to a small effective increase in mass of the photons due to frequency dependent interactions with the medium. I also read that the speed of light might be higher than through a vacuum if virtual particles could somehow be removed from a pathway in space conducting a beam of light. Does this mean that photons have a small mass due to the interactions with virtual particles, and the speed of light in a vacuum is not truly a fundamental value, and "C" must be revised upward to a theoretical maximum within a VP free enviornment ?

Having a conversation the other day about the speed at which space stations are depictded to be rotating in movies and whether or not the size of the craft is taken into account. Obviously angular speed will vary depending on radius but having watched people in human sized hamster wheels I would guess that the speed needed to effect 1g would be something like 10 to 12mph just to be clear I'm thinking if the circumference was 12 miles and it rotated once every hour that would be 12mph. I can't do the maths but I would appreciate it if someone could tell me at what speed a station would have to rotate to effect 1g Thanks in advance

I'm having some difficulty understanding why the coefficients of static and kinetic friction are constant e.g. they are the same on the Earth and the Moon. For example if μs = Friction Force/Normal Force then because the Normal Force is acceleration due to gravity dependent (mg) and the acceleration due to gravity on the Moon is less than that on Earth wouldn't this change the value of μs or μk, so they would be different on the Earth and the Moon? Here's the question that's causing my confusion;- A crate of 45.0 kg tools rests on a horizontal floor. You exert a gradually increasing horizontal push on it and observe that the crate just begins to move when your fo…

I know hovercraft struggle to get up hills, but what if they were faster? And if so, how would we be able to make hovercraft faster? Could we build one with jet turbines instead of the traditional gas turbine system?

Would it be possible with materials that can withstand it, to create plasma and propel and aircraft via superheated wings transforming gases into plasma and providing thrust through the expansion of those gases?

I have seen discussions on here and online about vacuum buoyancy and had 3 questions: 1. Can a vacuumed out cavity be created on earth or just less of what was vacuumed out? I ask because I am thinking that if you created a container underwater with water in it, if you try to evacuate all water from the container with a vacuum (not by pumping in air), what would happen to the water inside? 2. If a structure meant for vacuum buoyancy cannot withstand atmospheric pressure near sea level when a vacuum is attempted to be created, what would happen if that structure (while open) was taken up in a weather balloon where atmospheric pressure can be far less http://www.alt…

I was wondering what friction was caused by and why rough textured create more friction then smooth ones.

I am currently working on a paper on planetary magnetism and am trying to determine if there could be a theoretical way where one could somehow use the Earth’s own magnetic field to change it into one massive EMP that would instantaneously fry every electronic device on the planet. The only thoughts I have at the moment is maybe by somehow switching the polarity, however I’m not sure if that would create an EMP nor do I have an idea how one could induce that.