Manishearth
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 Feb 9 comment units and nature @SteveB The candela is only used to measure human perception (so not fundamental). Temperature, on the other hand, has a meaning and a use. Feb 9 comment What is your simplest explanation of the string theory? Obligatory xkcd: xkcd.com/171 Feb 9 comment What does Peter Parkers formula represent? @CaptainGiraffe Numbers this large do come into place when calculating possibilities . This is common in statistical mechanics. Feb 9 comment Should $E$ and $B$ change with Gravity? The LHC isn't "tracing the past", they're trying to simulate it at a smaller scale. "Tracing the past" has already been done with cosmic background radiation. Neither is the LHC simulating the entire situation. They're just doing high-energy collisions, and hoping for certain indications to come from it. They are not simulating highly curved spacetime. Feb 9 comment The maths/physics in “The Amazing Spider Man” The formulae look like probability formulae. So its most probably statistical thermodynamics. In that case, the sigmapiexp triad is pretty normal. Feb 9 comment Can a photon be emitted with a wavelength > 299,792,458 meters, and would this violate c? Even when SI units are specified, strictly speaking one cannot compare. I'm implying comparison of magnitudes. Feb 9 comment Countersteering a motorcycle Note: Centripetal torque will point perpendicular to the plane of the paper anyways. Torque $\vec{\tau}=\vec{r}\times\vec{F}$. It is a rotational vector, i.e. it points out of the plane of rotation. Feb 9 comment Can a photon be emitted with a wavelength > 299,792,458 meters, and would this violate c? Ive specified SI units to avoid exactly this discrepancy. The OPs question demands it anyways.. Feb 8 comment What causes destruction in car crash? Strange. @DavidZaslavsky Know anything about this? Feb 8 comment How can I explain why the weak nuclear interaction between individual nucleons is 'weak'? @annav From Wikipedia: "The fermi is named after the Italian physicist Enrico Fermi (1901–1954), one of the founders of nuclear physics. The term was coined by Robert Hofstadter in a 1956 paper published in the Reviews of Modern Physics journal, "Electron Scattering and Nuclear Structure"." enwp.org/Femtometer Feb 8 comment How can I explain why the weak nuclear interaction between individual nucleons is 'weak'? @annav $fm$ stands for both fermi and femtometer (they are the same unit). Yes, it's in honor of Enrico Fermi, though I don't know exactly why. Most probably due to his contribution to nuclear physics. Feb 8 comment What is the most efficient way to use hand dryer? Its a mixture of both. Fast air just means that it can supply heat faster. When a wind dries stuff, its the same concept. Evaporation borrows heat from the atmosphere. With a stationary atmosphere, the surroundings will cool but stop at some equilibrium value. With a current of air. There is no cooling of atmosphere, and thus evaporation can continue indefinitely till the water gets over. Alternatively, you can just supply heat. A dryer is a mixture of both blowing and heating. As such, I have dealt with the blowing in the heat equation, (as there is a time term in the equation given). Feb 8 comment What is the most efficient way to use hand dryer? The OP was asking for the most efficient way to dry your hands under a dryer. I doubt we are allowed to install a new dryer in the process.. Feb 8 comment What is the most efficient way to use hand dryer? The important thing is that any part of your hand should spend the same time underneath the dryer, regardless of the size. Of course, when rotating your hands, the shape of your hands does come into the picture (due to the $\cos\theta$ term) and makes the optimization complicated. Feb 8 comment What is the most efficient way to use hand dryer? First thing, its heat you want, not pressure. Anyways, I agree that its not effective in drying your palms, but it is required if you want to dry the sides of your hands. Read the third paragraph carefully. Feb 8 comment What is the most efficient way to use hand dryer? Of course, if you are talking about energy efficient , then its a moot point as most bathroom hand dryers stay on for a while after you finish (or turn off too early, in which canse you have to turn them on again). Feb 8 comment Superfields and the Inconsistency of regularization by dimensional reduction @Simon Maybe the people at enwp.org/WP:RDS could solve it? I'd ask it there myself, but I don't know the topic behind the question. Feb 8 comment How can a human eye focus on a screen directly in front of it? But the second approach (thin refractive layer) should work anyways, for both types of pixel elements. It will make the pixel's angular spread look as if it is coming from farther away. We only need a few centimeter's shift (stare at an LCD screen on low brightness from different distances); so we can get re-originate the angular spread without making the screen look too far away. Feb 8 comment How can a human eye focus on a screen directly in front of it? Well, yes. But angular spread will have to be minimized in any approach. It's pretty much a given that the pixel elements are not going to be conventional here. The OPs question was more related to focusing the light, so I didn't go into the details of crafting a laserlike pixel (Most probably it will involve polarizers and/or tiny mirrors). I'll add a little note. Feb 8 comment How can a human eye focus on a screen directly in front of it? Agreed, your method of putting two lenses seems like less effort. In that case we would just need to carve a thin slab in such a way the the front half (closest to your eyes) is a diverging lens.