As the speed of light is about 300,000,000 Meters per second and the speed of sound in air is about 340, yea, I would say that is well below.
Your hammer will only compress the rod if it is of sufficient size that the nuclear forces can act upon it. If your hammer happens to be a neutrino, then it goes right through the rod unencumbered. 😀
Speed of Sound in some common Solids
for single mode optical fiber the prop speed is basically c/index of refraction http://en.wikipedia.org/wiki/Optical_fiber
consumer TOSLink is multimode
for single mode optical fiber the prop speed is basically c/index of refraction http://en.wikipedia.org/wiki/Optical_fiber
consumer TOSLink is multimode
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It might be hard to mount a handle to a neutrino hammer. But if you could, we now know it would not only go right through the rod unencumbered; it would do so at speeds faster than light.
The speed of sound in the rod will be much faster than air, but still well below c. Speed of sound in air is almost entirely irrelevant to this problem.
Being disputed. Both camps have their arguments. I tend to fall back on nature being simple. The evidence of faster than light violates general relativity as it would need infinite energy if it had mass at all, and they claim a neutrino does have mass as it can only be detected when it hits a Hydrogen nucleus. That makes for ugly physics. Quantum entanglement poses another set if ugly problems. The experiments show both. I'll let them sort it out.
Dark mater does not pass my "sniff test" either but something has to explain the gravitational lensing. 11 dimensions? Brain intersections? Time only a construct? I bet the physics textbook printers are getting rich having to re-write everything every year. When I went to school it was simple Bohr atoms.
Second year Calc does mot make me privy to the math behind the Hawking Paradox, so I am left trying to read their over-simplified descriptions why you have to smear information on the event horizon and why you can't loose it at the center of a black hole. Fun to watch the arguments. My simple argument is that if you can't loose information, them everything is a fixed pattern and we have absolute predestiny. All we have to do is read the existing pattern and we can see both past and future perfectly. This conflicts with quantum uncertainty. What is a mere person to believe?
A caution to all, the WIKI is not always correct, complete, or up to date. These topics are changing daily. Still a great place to start.
Neutrino oscillation is the evidence for non-zero mass.tvrgeek said:
Actually, very little gets rewritten annually as the textbooks are always some years behind the research frontier. I have books from 30-40 years ago. Most of the physics in them is still valid. Newton's Principia is still essentially true, within its domain of applicability!
I remember the Bohr atom at school. I assume they teach that because it is a useful stepping-stone to full quantum theory, and does not require much maths. In the UK we now teach much less maths in school than when I was a youngster so proper quantum theory is even further from the grasp of a modern pupil.
In China they teach the math. We had better get our "stuff" together.
Cloud theory was pretty new when I took chemistry, so Bhor was what we had.
Hmmm, how do we detect oscillation if it has a habit of not interacting with much of anything? Still, if it is non-zero we hit the infinite energy problem unless space is not at all what we think it is. A more likely candidate.
Brain warp: Look where science and materials have gone post WWII. Now consider we still build houses out of trees held together with iron age spikes built on site, with paper and tar for a roof. I cook over an open flame. My shoes are made form animal skins. What is wrong with this picture! Maybe my coffee pot that has a processor in it to just boil water.
Cloud theory was pretty new when I took chemistry, so Bhor was what we had.
Hmmm, how do we detect oscillation if it has a habit of not interacting with much of anything? Still, if it is non-zero we hit the infinite energy problem unless space is not at all what we think it is. A more likely candidate.
Brain warp: Look where science and materials have gone post WWII. Now consider we still build houses out of trees held together with iron age spikes built on site, with paper and tar for a roof. I cook over an open flame. My shoes are made form animal skins. What is wrong with this picture! Maybe my coffee pot that has a processor in it to just boil water.
Well, most of this was pretty well worked out for chemists by 1933 or so. High school textbooks, not so much.
Well, when I was a freshman at WVIT, the prof was just leaving to write her book on cloud. That was '74. Text book and the national standard finals were still Bhor. OK, I guess it is time for a few W. Va. jokes? Actually, it was a pretty good school. I could blame Maryland schools as our chem teacher was more interested in the biology teacher, soccer team, and Spider Man comics than teaching chemistry. I think our text books were hand sewn and bound by Monks in the 14th century. When I got my assoc in electronics, Bhor was all they taught as it was a "technology" program. We still had RTL and DTL logic. Thank the powers that be for Discovery channel, Wiki, Google, Amazon, and the entire MIT program on the WEB! I don't have to feel old because I don't know erlang.
Perhaps it's Inigo Montoya time. 😀 I'm not sure what "clouds" you're referring to?
Generally when one talks about electron clouds (the most relevant issue in chemistry), one means things like probability distributions and (more conceptually) atomic and molecular orbitals. That stuff dates back to the early days of quantum theory- the Bohr view had been barely introduced when it was left in the dust.
Generally when one talks about electron clouds (the most relevant issue in chemistry), one means things like probability distributions and (more conceptually) atomic and molecular orbitals. That stuff dates back to the early days of quantum theory- the Bohr view had been barely introduced when it was left in the dust.
Ya' heard the one about the kid that got arrested at the West Va. border? He was charged with bringing a textbook across the line.
(In due respect to this being an international forum, humor intended for those with knowledge of US history, migration patterns, etc) Sy's reference is far more obscure. I am assuming he is indenting on perusing some level of attainment in a video game as it is too early for a Lone Star even in Texas. Either that, or this is related to a six finger sword. Refill on the java.
(In due respect to this being an international forum, humor intended for those with knowledge of US history, migration patterns, etc) Sy's reference is far more obscure. I am assuming he is indenting on perusing some level of attainment in a video game as it is too early for a Lone Star even in Texas. Either that, or this is related to a six finger sword. Refill on the java.
I remember hearing about 'clouds' and 'orbitals' in A-level chemistry in secondary school, around 1971. Our teacher got us to predict the likely properties of an element from its atomic number - it felt like we were doing real science. We also did things like 'sp3 hybridization' - which is something to do with covalent bonds? At university we went straight to the Schrodinger equation, via de Broglie matter waves.
sp3 is one of several ways to combine atomic orbitals to form molecular orbitals- in that particular case, most commonly for tetravalent carbon. It actually looks a bit like Ambisonics- the arrangement of atoms around the carbon is accommodated by linearly transforming the spherically symmetric electronic s orbital ("omni") with combinations of the p orbitals ("figure 8") in the x, y, and z directions to get four symmetric (to any tetrahedral point transformation) orbitals each pointing toward the vertices of a tetrahedron with the carbon atom at its center. There are called "hybrid" orbitals.
It's all mathematical construct, but with some very simple rules, you can look at molecular bonding at a higher level than solving (approximately) the Schroedinger equation. I have unhappy memories of some years spent trying to teach this stuff to unwilling freshmen.
It's all mathematical construct, but with some very simple rules, you can look at molecular bonding at a higher level than solving (approximately) the Schroedinger equation. I have unhappy memories of some years spent trying to teach this stuff to unwilling freshmen.
And this works because the s and p ground states are more or less degenerate in energy terms?
Once at university I didn't do much on bonding as it is not of great interest to physicists.
Once at university I didn't do much on bonding as it is not of great interest to physicists.
The three p orbitals are degenerate (by symmetry), but slightly higher energy than the s orbital. When you take linear combinations with the orbitals of the surrounding 4 atoms, you produce 4 bonding (lower energy) and 4 antibonding (higher energy) orbitals, with overall orbital energy conserved- and of course, the new orbitals are also orthonormal. But since each orbital accommodates 2 electrons (spin up and down), only the 4 bonding orbitals are occupied. That's why the chemical bond is energetically favored.
Ok,
Well if I put two pieces of card side by side put two holes in one piece and one in another...pass 1 photon through the first hole and two appear out of the other two holes the same mass as the one photon not two with half the mass of the original?
What is the mass of a photon?
Now I know I am not a mechanic... 😀
Regards
M. Gregg
Well if I put two pieces of card side by side put two holes in one piece and one in another...pass 1 photon through the first hole and two appear out of the other two holes the same mass as the one photon not two with half the mass of the original?
What is the mass of a photon?
Now I know I am not a mechanic... 😀
Regards
M. Gregg
If you put in one photo you will get one photon out, but it may come out of both holes. To split a photon you need some sort of non-linear mixer, and then the resultant photons will have lower energy than the input.
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