Phenomena Definition and 158 Threads

Hi everyone:) Is there anyone who has worked on the phenomena near the band edge of photonic crystals? for example spontaneous emission near the band edge? there are lots of articles specially from Sajeev John " spontaneous emission near the edge of a photonic band gap" Phys.Rev.A vol50 num 2...

1. Homework Statement Calculate the torque on the dam about the origin (Picture attached) due to the pressure force of the fluid. Homework Equations Pressure force is correct (dF) The Attempt at a Solution [/B] I have solve it; however, I am not sure if I calculated over the origin asked...

Hello guys, I'm curious in this phenomena: http://www.beaconlearningcenter.com/documents/492_01.pdf. In the second case, why don't the positive charges from pit ball move to the rod which is full of negative charges. If this happened, we would get a neutral rod and a negative pith ball... But...

The title might be a bit confusing but I just want to know if you can recreate (partial) the system of refrigeration with hydraulic compression. So say, you have a container (cylindrical piston) filled with water, then you apply pressure. Will the water's temp increase? Then, will the...

I have a new induction cooktop. I bought a pan rated for induction cooking for the stove and placed it over a burner while the stove was turned off. These pans tend to be rather heavy and the capacity of this pan was 3 qts. It had two handles, one was long and straight and the other was curved...

Hi there, can anyone please advise how the size of an obstructing object affects the propagation of an RF transmission? Eg, for instance does refraction only occur in objects that are larger than the wavelength or does it occur in objects smaller than the wavelength? I can find heaps of info...

Hey! :o Do you know if "Wave Phenomena" are related to PDE or only to physics?? (Wondering)

Hello! Just came across this video, . Does anybody know how to explain this?? Best Regards Kontilera

Hi everyone, Can someone please explain to me what happens here? Why does the polarity reverse? My friend explains it like this, I quote: "as opposed to what is taught in schools, magnets have a centralized force field". Is there something to this? What happens here...

i was given the question below, and have submitted my working but i cannot move forward from where i stopped on the photo Consider the diffusion equation (with source) u_t (x; t) - Du_xx (x; t) + ku(x; t) = 0; 0 < x < ℓ; t > 0; under conditions of zero-flux at the boundary points x = 0, x = ℓ...

Hello. I played with my new, first ipad yesterday. I inverted sceen colors and activated the cam. How comes there is an image of me reflected in my eyes with NORMAL colors?

Hello, I work for a class 1 railroad in northwestern Ohio as a conductor. Approximately six months ago traveling down the tracks at a speed of 45-60 mph, en route to Pittsburgh, PA, my engineer and I encountered something bizarre and, for us, baffling. A light beam from every single light...

I was playing my old pinball machine today when the display started to malfunction. After several minutes, the dot matrix display shows only a horizontal stripe as shown below. The interesting thing is that when I move my eyes vertically over the horizontal stripe on the display, I am able to...

Hello, whilst making my coffee this morning (more like this afternoon, but hey I'm a student), I noticed something that I thought was cool and I'm interested in hearing what you guys think may be happening and/or what you have to say about my ideas. So, I have these 'coffee filters' that are...

Hello, Just discovered this forum as I'm so intensely curious about this question I sought out just such a place! I'm currently designing a circular patio using 6-in square blocks in concentric circles. While using a combination of Excel and Adobe Illustrator, I uncovered something...

Hello, everybody: I was wondering if you knew if there is a book, journal, webpage or a compendium of some sort in which different and diverse curious common and uncommon natural phenomena are explained with physics (preferably with math involved). For example, a place where to look if I'm...

Since I couldn't start a thread in the learning materials section , I thought this would be a suitable place. I am searching for some sort of Encyclopedia , as the title suggests , I need a Physics-Encyclopedia which covers quite a lot of ground(Classical Physics to Modern Physics). The main...

I am using a computational electromagnetics software that solves for the resultant electric and magnetic fields around materials represented as lattices of discrete dipoles. Some of the results are the extinction, absorption, and scattering efficiency factors of EM waves, represented as a graph...

Inspired by the song, this little montage I put together collects some very cool science (and science fiction) related imagery to get students excited about the phenomenon of science. Our school used it for our recent science festival day. Enjoy and pass it on!

when i rotate a screw at low speed he stop after sec. but when giving him high initial speed he rotate,stop,and rotate backwards and stop again. i think its because the drag force which got 2 components,1 take care of low speed velocities and the other high speed. i'm not fully understand...

I found the http://gowers.wordpress.com/2012/11/20/what-maths-a-level-doesnt-necessarily-give-you/ interesting. Curious that his example was the same one I was asking about. He makes the distinction between teaching how to understand math and teaching mechanical manipulations (my cheap tricks)...

I was working on this college project in optics, and I was thinking of ways to preserve light by multiple reflections. The question is, if I manage to coat a transparent glass (or acrylic) rod with a reflective layer (via silvering), will the internal layer of the rod be reflective as well or...

Please help; Explain phenomena about collision and water. click Now>>>>http://vimeo.com/29207632 thank you...

Author: R. Byron Bird, Warren E. Stewart, Edwin N. Lightfoot Title: Transport Phenomena, Revised 2nd Edition [Hardcover] Amazon Link: https://www.amazon.com/dp/0470115394/?tag=pfamazon01-20 Prerequisities: Advanced Calculus, Differential Equations (ODE, PDE), Introductory Heat Transfer...

I am a graduate student in physics. Can someone recommend a book that explores transport phenomena or diffusion from a physical sciences (instead of engineering) point of view? I would like that because I'm not dealing with industrial equipment and don't want to spend chapters wading through...

Are there any known examples of colliding stars? has the phenomena ever been observed? tex

Homework Statement I was doing an experiment to verify faraday's law Where we were basically dropping a magnet through a coil and measuring the induced emf Now here is the thing I can't explain; we connected 2 coils in series and found the induced emf was the same as that of one...

Homework Statement My problem is that I can't remember a certain psychological effect. Homework Equations N/A The Attempt at a Solution I remember reading up a certain phenomenon, or effect of brain. The brain when viewing an image becomes ''imprinted'' into the mind. When that...

Just out of curiosity, is physics (advanced or theoretical, not simple classical physics like thermodynamics or mechanical properties) ever used to model, solve, explain, or apply to medical or biological (human) systems? I know hemodynamics and neuroscience involves a lot of math based...

I have recently started my phd on ab-initio simulations, and have several confusions about the calculations (lets say with a method like DFT) of solid crystal structures. 1. what exactly are the exchange and correlation phenomena. I have read texts and books which describe its physical...

Homework Statement 13. A man standing by the shore observes sea waves approaching at a frequency of 0.20Hz. A man on a boat observes that waves are approaching the boat at a frequency of 0.50Hz. The speed of the waves is 2.0ms–1. Which of the following gives a possible value for the speed of...

I have just had a short discussion with somebody online about how some scientific terms are hugely misleading due to some historical misunderstanding. The example that I put forward was the term 'planetary nebula', which was originally given to objects that looked like planets in poor quality...

I was doing a question while back about finding the de Broglie wavelength of a bullet with a given mass traveling at a given speed- easy stuff. However, when the result was very similar but slightly larger than the Planck length which I'd stumbled across on my few jaunts through Wikipedia, it...

I am facing a problem on transport phenomena. Can anyone help me to solve this problem. I would really appreciate it. Its little urgent. I know that i have to use shell mass balance to start the problem but how to proceed further is what making me confused. In a beaker, a solid sphere of...

http://en.wikipedia.org/wiki/Exponential_family I can't count the number of times I've encountered exponential trends in my daily life: - Productivity - Skill differences - Wealth differences Not even all socioeconomic: You can even find it in nature: - the energy amplitude of an electron...

I can't count the number of times I've encountered exponential trends in my daily life (productivity, skill differences, wealth differences) not even all socioeconomic...you can even find it in nature (the amplitude of an electron decreeasing exponentially as you get away from the center)...the...

Can someone confirm this as true or as crank-science. I tried looking for any publication of this but haven't found anything. "They were trying to establish exactly how organic photosynthesis approaches 95% efficiency, whereas the most sophisticated human solar cells operate at only half...

Hi, I am learning about refraction and the million ways in which Snell's Law is presented to me is making me confused... So, I understand that: sin i / sin r, will give me the ratio of speeds ci/cr and λi/λr However, I can't understand this form of: n1sin i = n2 sin r How does...

What's the physics behind it?

Iwatch a very thin stream of oil falling from a pipe & into another pipe thru 1' of airspace. It looks like a stream until i abruptly twist my head horizontally [snaplike] & then i see droplets instead of a stream while my head is rotating [snaplike].

Homework Statement There are two bodies colliding Simulate the collision phenomena by numerical integration. (1) Confirm that the total kinetic energy is conserved if you ignore the damping forces. (2) Show that the total kinetic energy is reduced through collision if there exists any...

Can loop quantum gravity tell us something about the recent phenomena of the neutrinos?

Can someone list some of the phenomena only explicable via QM?

Is Pauli exclusion principle due to magnetic interactions between spins of electrons?

Greetings and salutations. Today I bring with me interesting phenomena, which I managed to reproduce and photograph in detail. I noticed one when I was enjoying my ~300mW 532nm laser in a dark room, if I reflect the beam off a regular plane mirror with a small angle, it projects 2 separate...

I'm not physicist, but a software developer. Please don’t hang up.:smile: I am building massive multiplayer online game server, and I started building it from scratch. I found that some programming issues emerged from it which had striking resemblance to quantum quirkiness, so I just wanted to...

http://img820.imageshack.us/img820/8610/triangler.jpg I know that if I could apply force F to meet in a single point with the normal force and the tension, there would be no need for friction for equilibrium. Why? What's the physical explanation to this phenomena?

Can/do relativistic effects explain select quantum "phenomena" Can/do relativistic effects explain select quantum "phenomena"? A photon (a mass less "particle" that travels at the speed of light) experiences space-time in a different manner. A photon does not experience time. Would the sun...

These videos were recorded at Angicos, a small town of Brazil. They are records of the same phenomenon. Can someone identify it? A tornado? A gustnado? A dust evil? https://www.youtube.com/watch?v=nwmngFGhGqQ https://www.youtube.com/watch?v=x_LQ0aevpZk...

I have a question about quantum coherence phenomena. I understand (basically) how laser light results from light waves that are in sync. I also see how ferromagnetism results from orderly alignment of electron spin amongst iron atoms (though I've posted in another thread asking whether this is a...