Ragnarak

indeed at the minute we don't want to break it as it's completely encased in the plastic (?) case if we were able to break it we could measure the dimensions of the semiconductor and then apply capacitance/conductivity equations to it this along with the data we have wouldmean we could get 2 3D graphs which would have 3 intersecting planes that would then yield the composition for a single va,ue of energy gap but it means breaking open and potentially damaging the diode :/

I have a problem i just can't get my head around and wondered if anyone here had any ideas. We have a set of LEDs and are required to find out what the composition of them is. They are made up of a mixture of Aluminium, Gallium and Indium but we don't know in what proportion. There are 3 different LEDs that give three different colours; red, yellow and green. These 3 all have a different mixture of Aluminium, Gallium and Indium. Is there any way that anyone could suggest to determine the exact composition. So far we've found the band gap energies via several methods. Spectroscopy and IV characteristics have both given us values for the energy gap but we're not sure how to progress from there. Any help would be greatly appreciated

been a while since i read that book but what context is he talking about this in? (the artificial intelligence/computer mind isn't it?) wouldn't that be an example? when i read it i understood it to imply the same as you

no it's based on having the best chance of surviving they are quite different things if you think about it

er does it? been reading a bit about higher dimensions, a bit about parallel universes and black holes but not seen any mention of infinite energy...? tho i admit i know extremely little about super string theory which is what it was mostly based on :/ (dudels: infinity/2 = infinity)

parallel universes ahoy Just read a very nice time travel paradox about a person who was their own mother, father, daughter, uncle, etc. If i get time i might type it up later

For basic calculus? If you managed a B or above in GCSE* maths you can definitely handle the trig/algebra. It's a lot easier than coding PHP ;p Calculus is extremely easy at any level you'd do it at before university. (*i know you're in the UK so put it in terms you'd understand, sorry to all the yanks )

heat is the transfer of energy due to a change in temperature ie. convection, radiation, etc I think that's the simplest way to look at it. ps. why can't we delete posts? i accidently quoted this one instead of editing it

gravitons no 'r' they are the (theoretical) exchange particle for the gravitational force i think mass causes the curve in spacetime and gravity IS the curve tho i haven't really looked at any general relativity yet :/

If you're using XP download the latest service pack or Download the jdk or sdk from the Sun website, it should contain what you need.

oops forgot to add cosmic background radiation is microwave radiation

Heat is a form of energy It can be transmitted through space Waves transfer energy from one point to another I think we may be getting into the territory of wave/particle duality thinking.

both? temp is measure of average KE of particles heat is a type of energy related to motion of particles

ok then, slight addition to take into account not just the element but the ions too: no. of electrons = (no. of protons) - (charge on ion*) *which is 0 for stable elements

thanks for that the maths is fine and i pretty much understand what i'm doing, it's just there's no easy 'mental picture' to use

basically as already stated: no. of protons = no. of electrons = atomic number ie. 11 no. of neutrons = 'what's left after you account for the protons' = atomic mass - no. of protons ie. 23-11

Deep space has a temperature of 2.7k i believe, which is, as stated above, due to the cosmic background radiation

heh we believe you, honest (seriously thanks for the effort at least )

"sensitive dependance on initial conditions" is the phrase i meant to add to that. it would require an infinite (ie. impossible) amount of information to be able to predict exactly what would happen.

I don't think that would be the case. There is chaos involved in everything from turbulence to heat dissipation. No two universes would be exactly the same. Again i am arguing from a very very small amount of knowledge on the subject so could very well be incorrect.

I'm in 2nd Year of university, tho the course is a third year course. (Without going into detail, anyone not amazingly stupid 'accelerates' and takes courses from the next year to give more choice of doing different options the year after) It's a QM course within a physics degree.

We're studying QM at the minute and it's quite easy to visualise the superposition of wavefunctions in 1 dimension and not that much harder in 2 dimensions but when it comes to 3 dimensions it seems to be much harder to visualise the wave functions. The closest analogue i can think of is prolly some sort of lattice but instead of points at the intersections it's more like 'blobs'. Does anyone have a better way to think of it?

I don't know enough about Chaos Theory to argue with this properly but i'm almost certain that is incorrect. Even with a simple system with well-defined laws, chaos theory means long-term predictabliity is impossible.

yes so: "integral of uv is uv - intg(v*du)" is not right it's: int(u*dv) = uv - int(v*du)