Broken Definition and 124 Threads

We all know that M.I of a Uniform rigid rod about an axis perpendicular to it's length and passing through it's center is MLsquare/12.Where M is mass and L is length of the rod. If it is broken to half such that M becomes M/2 and L becomes L/2,we can't apply ML square /12 formula to it.We have...

Hello. I just got a PMT the glass bulb of which has been broken. Even if performances are not the best, do you think I can use it as an Electron Multiplier (with all convenient electronics) ?

I have read 2 arguments that a gauge symmetry cannot be spontaneously broken. 1. Wen's textbook says a gauge symmetry is a by definition a "do nothing" transformation, so it cannot be broken. 2. Elitzur's theorem, eg.http://arxiv.org/abs/hep-ph/9810302v1 The first argument seems sound...

Hi, Supposed the ground floor of a building needs to be raised 2 feet higher with respect to street level. How good is using broken concrete as fill versus putting soil? I heard one needs to compact the broken concrete. What do they exactly do when they compact it? Would the overall cost be...

If : The total energy of a falling rock = G.P.E. (mass x gravity x height) + K.E. (0.5 x mass velocity^2) But if a rock reaches terminal velocity (i.e velocity remains the same) but height keep decreasing, then surely Kinetic energy is remaining constant and Gravitational potential energy is...

Thought this link may be of interest. http://www.stuff.co.nz/science/6933974/Teleportation-record-broken

I had a look at Jackiws article on axial anomaly in scholarpedia: http://www.scholarpedia.org/article/Axial_anomaly Apparently, axial anomaly also breaks Lorentz invariance. Even if this effect would be very weak, doesn't this pull the plug on relativity?

I quote from my book: "Just after the switch is closed, the inductor acts to oppose a change in the current through it." "Because the current through each inductor is zero before the switch is closed, it will also be zero just afterward. Thus, immediately after the switch is closed, the...

"... a man is broken, a horse splashes." "You can drop a mouse down a thousand-yard mine shaft and, on arriving at the bottom, it gets a slight shock and walks away. A rat is killed, a man is broken, a horse splashes." — J.B.S. Haldane, biologist No surprise there, given that the bigger the...

Spontaneously broken R-symmetry is a sufficient condition for spontaneously supersymmetry breaking. My question is: What is a spontaneously R-symmetry breaking?

There has been a suspicion that solar neutrinos can interfere with the rates of radioactive decay in isotopes. Could this mystery (somehow?)be tied to the neutrinos that are being recorded as 'faster than light'? For example the neutrinos pick up extra energy from the radioactive decay...

Dr. Hughes, an Australian physicist has taken exception to the Oxford Dictionary’s definition of a siphon, http://www.telegraph.co.uk/news/worldnews/australiaandthepacific/australia/7709513/Physicist-spots-99-year-old-mistake-in-Oxford-English-Dictionary.html" claiming that a siphon works by...

Homework Statement According to the molecular biology book I am reading, when a chemical bond breaks, the energy in the bond is released in the form of heat. which is to say, when a chemical bond breaks the entire atom's speed increases (the atom gains 'heat energy'). But what is...

Speed of light broken?? I do not know if there is a topic on this but has anyone heard about the findings of how physicists have found neutrinos that traveled faster than light speed? Here is the link, I'm interested in what the PF community has to say! I think it is just systematic error but...

A simple paradox - Imagine something falling into a black hole, starting at infinity. When it gets to the event horizon, its velocity has to be c. However, from the perspective of an observer outside the event horizon, its mass has become infinite, which means it would also have an event...

Has anybody heard of this? http://www.telegraph.co.uk/science/science-news/8783011/Speed-of-light-broken-by-scientists.html

I thought I had a good understanding of transistors, but I have seen articles on how to tell the collector from the emitter. I had always pictured transistors as a perfectly symmetrical device. Either side could be the collector, and the opposite side was the emitter. Clearly, there is some...

Hello all. I was inquisitive whether a diamond can be broken by a hammer. I think it can be, because diamond is the most hardest material found, and hence the most brittle which can crack when hit by a tough and comparably hard material. If I am wrong can someone highlight how diamonds are cut...

Please teach me this: In linear and nonlinear sigma model, the spontaneous symmetry broken is inevitable happened or it may be happened and it may be not happened?Because the expectation value of field may be zero or may be not zero,then it seem that sometimes the hidden symmetry broken not...

Hi, Everyone: I hope this is not off-topic; I apologize otherwise. Just went through hurricane Irene; luckily nothing major happened. Just curious, tho, about the issue of windows, and how to prevent them from breaking; I guess this has to see with the pressure difference...

Hi, I am interested in grand unification with extra dimensions. Especially the case when extra dimensions are broken by orbifolding. Now I am trying to understand how the Goldstonebosons appear in the spectrum of a theory with global (for example SU(N)) symmetry. From the...

I guess this goes under engineering, but if not then whoops. I sat down hard on a wooden chair recently and heard a loud snap noise. I discovered that the wooden pegs that connected the right seat support to one of the back legs had snapped. So I pulled the chair apart and drilled out the...

Please teach me this: Do the Lagrangian(before broken in symmetry) and corresponding hidden symmetry broken Lagrangian describe the same physics or not?Because the field in the Lagrangian before broken is shifted by a constant in comparision with the field in the broken Lagrangian,but at...

it is obvious that the hamiltonian of an atom is time reversal invariant but how can an atom have non-zero magnetic moment?

So in my mechanics of materials class we were taught about stress-strain curves. I asked a couple of times for the meaning of the broken diagonal line on the graph but no one seemed to give me a logical answer so I decided to ask here.

Homework Statement Sketch the function: f(x) = \begin{Bmatrix} \frac{-x}{a} & 0 \leq x \leq a \\ \frac{x-L}{L-a} & a \leq x \leq L where f(x) is an odd function and is periodic in 2L. And a is a constant less than L/2 Find the Fourier series for the function f(x). Homework...

Homework Statement You have paid big bucks to see Season of the Witch at the 3-D IMAX theater in Vancouver. Just before the movie is about to begin, the theater staff tell you that the lens for the projector has just broken! You really want to see the movie and decide that it should be simple...

What do we mean by "broken symmetries" when referring to superfluid he3 phases? I struggle to understand the concept of broken symmetries of the superfluid phases of 3He. Any insight would be much appreciated. Thanks :)

Traveling along a back road to my village i hap-end across a huge limo with two Arab sheiks standing beside it, i stopped and asked could i help them, one of them said the car is making a strange noise, i looked it over and found one of the rear springs had broken. I told them that i could take...

The common understanding is that below around 250Gev the weak force gauge bosons have mass and appear distinct from the electromagnetic force, with its massless photons. And that to explain this required hypothesizing the Higgs field, which acts like a superconducting field, in the vaccuum...

According to this recent paper: http://arxiv.org/abs/1010.4886 The graviton of the new spin foam models fall like 1/r^4 and not like 1/r^2 as it should be. Is it that bad?

Homework Statement A plane of a mass 5000 kg moving horizontally in 150 m/s break into two parts 2000 kg and 3000 kg because of a internal explosion. If the bigger part be thrown away with a 400 m/s relative to other part to opposite direction of previous moved direction before explosion...

I have some good news and some bad news. First, the good news is HTML5 includes MathML and has been embraced by all browser vendors. Now the bad news. MathML support is broken in IE9 and we see no evidence that Microsoft will fix this problem unless they are made to understand how...

Friday morning I was sitting at my desk when I felt this burning sensation in my left hand. Suddenly the middle joint of my index finger started swelling up and it was very painful. Then the middle joint turned purple and looked like it had been hit with a hammer. It's been two days now and...

Every single GOP candidate for governor (Primary is next Tuesday) is saying the same things. "I will create jobs, I will cut taxes, and I will cut wasteful spending." It all sounds so rosy, but how can a governor create jobs? Most of them, if pressed, will say that they will create jobs by...

I read from several sources that the loudest sound ever made is over 200dB either from earthquake or *insert powerful bomb name here* explosion. Unforunately I don't know at what distance these volumes are measured. I thought for every speaker you add, you gain 3dB. If they're co-located, it...

Homework Statement With what program (freeware) can I draw a graph with broken y-axis. An example of what I want: I know that this is possible by using Excel, but just in a very cumbersome way, right? Thanks in advance.

Hello, Now that there's only one week left until the LHC starts working on the collisions, I think it's a good idea for me to ease my mind and ask how will they observe superparticles and discern them from the SM particles.

How’s your snow blower these days? We got 24” of snow a week back and more yesterday and today. The skiing at Blue Mt was FANTASTIC yesterday! But my snow blower regurgitated a rock and left me stranded. The fix is easy, so I thought I’d pass this on to folks that might have a similar...

This press release makes it sound like a big deal: http://www.bnl.gov/rhic/news2/news.asp?a=1073&t=pr On the other hand, this seems to be the paper, http://arxiv.org/abs/1002.1641 and it never even seems to mention P or CP breaking. Anyone know any more about this? I'm not even sure if...

Homework Statement I'm looking through some old IB exams, and I came across this (supposedly fairly easy)question. I'm having some problems, and I feel there's something really basic I'm missing. http://img52.imageshack.us/img52/5139/physicsproblem.jpg...

I am struggling for some time to understand the concept of broken symmetry. As I come more from the solid state side than from high energy physics. My problem is the following: I understand, how e.g. the rotational symmetry in a ferromagnet is broken. The magnetic moment is observable and I can...

Momentum "Broken Plate" Problem Homework Statement By accident, a large plate is dropped and breaks into three pieces. The pieces fly apart parallel to the floor, with v1 = 3.10 m/s and v2 = 1.95 m/s. As the plate falls, its momentum has only a vertical component, and no component parallel to...

Homework Statement I believe there is some kind of glitch in my Interactive Physics program. The screen shot below is supposed to be the result of applying an 8N force at 30º above the horizontal, from the left. My knowledge(?) tells me that a portion of that 8N is going to be expended...

i think mirrors reflect light and light source 1 with x energy is reflected by the mirror which uses some of that energy to create a double of that light source and thus creating light source y. is light being created? PHYSICS IS BROKEN. LOOK TOWARDS THE SKY IF U CAN SPOT THE TEAR IN...

http://www.popsci.com/military-aviation-amp-space/article/2009-03/hurricane-busters

Homework Statement How do you know whether you restrict the domain or range with a horizontal ellipse ? Homework Equations x^2/49 +y^2/10=1 The Attempt at a Solution

Broken code -- UAC related? Here's the code I'm having trouble with, cut down the relevant part: protected void ProcessFiles(string[] files) { if (File.Exists(outputFilename)) throw new Exception("Output file " + outputFilename + " already exists!"); if...

Broken nose? I think I have broke my nose several times, but I'm not sure. I have several lengthy stories as to why I think so, too, but now I have a bump on the top of my nose where it looks like the bone is pushing up or something. It used to hurt but this has been several years ago, so I...

The propagator for gauge bosons in a spontaneously broken (non-abelian) gauge theory in the R_\xi gauge is (see Peskin and Schroeder eqn. 21.53) \tilde{D}^{\mu\nu}_F(k)^{ab}=\frac{-i}{k^2-M^{ab}}\left[g^{\mu\nu}-(1-\xi)\frac{k^\mu k^\nu}{k^2-\xi M^{ab}}\right]\,, where M^{ab} is the gauge...