BhavinB

If we stick to the definition that nanotechnology is construction on a sub 100 nm scale, then there are some interesting statistics. For example, common myth is that nanotech is leading to robots on that scale, when rather the majority of research and spending is more towards materials with 'nano' properties (Like nanocrystalline materials). The next biggest research area in nanotech is nanofabrication i.e. electronics. we're well into that regime with intel already setting up a 65 nm fabrication process. But in research, linewidths of 10 nm have already been reliably fabricated. And then there are some people working on...robots. But be aware, all these robots are stupid and cannot be controlled. Having controllable 'robots' will not be realised in our lifetimes.

^^ good answer. I actually thought his question implied "Can EM radiation damage a material enough that it becomes radioactive?"...To which the answer is also no (for most materials).

Ya, I'm not in the field, but I'm sure you can easily find the information with any university library account. But just conceptually, you'd need a certain concentration of ATP, not mass. Plus, the active components of any device will have something similar to cells and proteins to convert the ATP. B

There are ways of powering things with ATP. Go look up chemical motors. Friend of mine is working on a linear actuator powered by ATP.

There are inefficiencies and probabilities (related to chlorine concentrations) which play a role here. 1 mole of light will in no practical way beak one mole of chlorine gas. As to answer your question though...both the valence electron states and the nuclear vibrational and rotational states play a big role in how light is absorbed by a molecule.

Yes, light can cause vibrational and rotational excitation in molecules. However, perhaps the answer you're looking for is that every material can have their 'most likely absorption' energy band and their 'most likely emission' energy band in different regions. Usually, energy can be transferred in excited molecules internally through vibration and then have the remaining energy re-emitted at a different wavelength.

If you assume all the particles are non-interacting, then yes you can do that. Although its useless to know the volume of one gas in a mixture. Its more useful to know its pressure...which is known as the partial pressure. However, many gases interact. In this case, there is a deviation from the ideal gas rule upon mixing (which assumes a uniform gas of one type of molecule).

No, Lance is right. LED's have less power density compared to those bulbs. Eventually they will be comparable. That'll be around the time LED illumination to light houses and stuff will begin. But for now, LED's just don't cut it for lighting a large area such as a wall for projection purposes.

me neither What branch of physics do you study?

Are you asserting also that a neutrino is its own anti-particle? B

'opposite' implies a linear negation. However, a true definition of antimatter is far more complicated. I'm not an expert to say what that means however. But to say all neutral particles are their own anti-particle is an incorrect statement. ex: Neutron and anti-neutron

http://hyperphysics.phy-astr.gsu.edu/hbase/particles/neutrino3.html#c1

There is a quantum mechanical derivation of Zeff based on screening potentials of electron clouds. I don't have the actual equation on me right now, but its a nasty integral. B

Drink alot of orange juice. Lead Citrate is a more stable complex than some of the other harmful complexes in your body. Plus Lead Citrate will leave the body in your urine. Lead refineries have been giving their workers Citrate drinks for a long time now to protect them from accidental exposure. This is just a precaution...you still don't wanna be exposed at all. B

There's an FAQ website about this guy. Just search his name. He goes and posts the same thing on every newsgroup he can find but as we can see, he rarely replies back.

I have a friend that mixes red bull and whiskey. Lets just say he was extremely hyper for a few hours at a party and we have humorous videos of him dancing like a moron

I was careful to use the word "frame of reference" just because that relates to relativity. However, if you want to go really deep into why there is invariance, then look up anything and everything you can find about Emmy Noether. She was a mathematician who proved that due to space-time symmetries, certain laws of physics are invariant. Further, General Reletavity has a few concepts on point-of-view invariance which render your theory mute. Should be good reading... B

i've never actually read the paper, but I've heard that not too long ago, someone in physics has proven that in any given reference, there must be universality in position (ie some other position in the universe in the same frame of reference must follow the same laws as we derive here). Which means there must be a time constancy as well. Saying that time has its own velocity at some other position in the universe is an interesting thought, but there is no basis for thinking that.

There are positive ions and negative electrons in a plasma. If the electrons travel on one helix the ions will travel the other.

well, suppose you have two functions, f and g which are functions of x. Now also suppose that as x goes to zero, f approaches infinity and g approaches zero. Now if I define h = f/g, then what is the value of h at zero? Its infinity over zero. Luckiliy calculus gives us a way of figuring out sticky situations like this using L'Hopital's rule. We can then figure out if in the limit x->0, what does h approach. Is it infinity, is it zero or some finite value. http://mathworld.wolfram.com/LHospitalsRule.html the rule also works for situations involving inf/inf, 0/inf, 0/0 etc

The kinetic theory of gases (atoms) assumes an ensemble of N non-interacting particles in a box of volume V. The key is the word "non interacting". This assumption is not true for say water because there is heavy interaction through hydrogen bonds. A more accurate model will show that the kinetic energy of of water (in thermal equilibrium at room temperature) is not enough to break all the interactions that keep the water as a liquid.

http://en.wikipedia.org/wiki/Michelson_interferometer The dark zones in the resulting image are where light destructively interferes. There are a few famous interferometers. I'd say the most widely known is the Fabry-Perot interferometer, just cuz the concept is useful for lasers, filters etc... B

lol... w=f.d where bold values are vectors and the period is a dot product. The dot product can be rewritten as follows w=f*d*cos(x) where f and d are the magnitudes of f and d and the value x is the angle between the two vectors. The * signifies scalar multiplication.