# Tag Info

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This document (NB it's a pdf) contains details of the beam operation. Here's a key graph nabbed from the presentation: At the end of an experimental run the beam is dumped, and it takes about an hour and a half to get the beam back up to full energy and intensity. Once the beam is at full strength the LHC generates data continuously for somewhere between ...

6

Pressure is force per unit area, yes, but it also represents the difference in kinetic energy density across a surface - only the energy of random motion of particles, though not large-scale coherent motion like wind. Accordingly, the faster a fluid moves, the more of its kinetic energy goes into large-scale motion, and the less is left for random motion of ...

5

I was working at CERN bubble chamber experiments back in the early seventies. The accelerators required a vacuum so as to be able to sustain the beam which makes many turns in the circle ( practically velocity of light), so the best possible vacuum is and was a necessity. After the generation of the beams , the beam lines did not need a vacuum because the ...

5

I'd expect you run it for a few seconds and bam - higgs boson detected or whatever. How does one detect the Higgs Boson? That's the question you must consider. Since a real Higgs almost immediately decays upon being produced, all we can detect are the stable decay products, those particles that last long enough to leave the vicinity of the collision ...

4

We know what the solar neutrino spectrum looks like from direct measurement (Super-K has even imaged the sun in neutrinos). Likewise we know what the spectrum of neutrinos coming from cosimc ray interactions in the atmosphere and the body of the early looks like. And the spectrum for our nuclear reactors and that from the uranium and thorium in the deep ...

3

Bernoulli to the rescue! Does this answer the question? Keep in mind, hurricane speeds are often twice small aircraft stall speeds, and typical aircraft wing loading is in the range of $50 kg/m^2$, so a roof could see 4 times that. Roofing material would have to be really heavy not to be lifted by that.

2

The experiments take many years. Using the Higgs boson search as an example, the reason it takes so long is because there is no "smoking gun" signature of a Higgs boson. You don't search for the Higgs boson directly, but for the Standard Model particles to which the Higgs decays. Since other Standard Model processes (called "backgrounds") can produce these ...

2

There's actually a FAQ for the LHC (CERN approved too). In that link , you'll see your exact question with the answer (all emphasis mine), When a proton leaves the source, it crosses the linac and reaches the PSB in a few microseconds. In the PSB it is accelerated from 50 MeV to 1.4 GeV in 530 ms, then after less than a microsecond it is injected in ...

2

The molten tin won't cool evenly because the cooling is at the surface of the container it's in. Your solidifcation will start at the outside and crystals will grow inwards. You will get a temperature gradient in your tin. This effect is more marked with faster cooling, so keeping the cooling rate as slow as possible will give you a sharper liquid to solid ...

2

From a measurement point of view, it might happen that by cooling too fast you don't see the transition. Another element could be that you cool down to a quenched state which is not the solidification you are hoping but more like into a glass state.

2

This is similar, but not quite identical to Newton's cradle, with the difference being the heavy objects placed on the middle coins. To explain things, first consider the simpler case where there is no heavy object on top of the coins, and suppose the 5 nonmoving coins in "frame 1" are separated by a distance $L$. When two objects of mass $m$ and ...

2

It's been a decade since I last used an SEM, but back then you would start using a fast scan that was real time i.e. you could move the sample around, change focus, etc and see the effect in real time. However the realtime image is noisy because the numbers of electrons being captured is small. Once you had the picture you wanted you would record them image ...

1

There is no universal, cheap, easy way to do identify unknown materials. There are some easy methods that apply to some materials: if something is attracted to a magnet then it is ferromagnetic, and probably contains a substantial amount of iron, nickel, or cobalt. There are a few other rules of thumb, but the general problem is complex and is the reason ...

1

Well, the fancy experimental way would be to use things like mass spectrometry or x-ray diffraction, or many other techniques. Doing it without those machines though... maybe chemistry would be your best bet. If you had a suspicion of what the material might be, you could use known chemical reactions to see what it does and doesn't react with, what it ...

1

Refer Bernoulli's Theorem. Watch this video for demonstration http://dornsife.usc.edu/labs/lecture-support-lab/wind-storm/. Brief explanation: When the velocity of the wind is great enough, the air pressure above the surface is lower compared to that underneath. This cause the roof to blow off. The aeroplane work in the same principle (lower pressure on top ...

1

Scalar fields do transfer momentum in classical physics. Just take a look at acoustic signals in a gas. A strong sound can cause your windows to rattle. A well known example of energy transference by means of sound (pressure waves) is demonstrated with tuning forks. Quantum theory speaks of sound as particles (phonons), the discrete quanta of quantized ...

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