Levels Definition and 499 Threads

When the depth of a quantum well increases, the first level increases or decreases its energy with respect of the bottom of the quantum well?

Hi there! Does anyone here know what the typical light levels are at the Martian surface (in daylight hours!) and how they vary in magnitude through time? I'd prefer a measurement close to the equator, but I'd be happy with one from anywhere at the surface. I can easily calculate the...

Six days ago, the Dutch government added a flight fee at Schiphol, the Amsterdam airport, to be used to lower Earth’s atmospheric carbon dioxide (CO2) levels. The Netherlands is one of the four countries that tax carbon put into air in response to advice from the UN-sponsored Intergovernmental...

I've been researching the change of energy levels of electrons when excited by photons. The equations I have found are... E_n = (-2pi^2 * m * e^4 * Z^2)/(n^2 * h^2) Which gives us the energy of the electron at a particular energy level. m = mass of electron e = electric charge of...

In many textbooks and sites of solid state physics energy levels for the free electron approximation in band calculations are displayed. The result is a collection of many parabolas, each of these parabolas being centered on a site of the reciprocal lattice. This is not anyway the picture that...

I know this question seems very simple which is why its bugging me so much: Why is the ground state energy not zero? A simple answer would be greatly appreciated

I have had a pressing question haunting my mind for quite some time, and I need an expert opinion. My car calls for premium fuel (2007 Honda Civic Si), yet states (in the owners manual) not to use gas below the octane level 87. Now I purchase my gas from Sinclair and the octane levels read...

Homework Statement I'm just wondering how you get the energy levels from the Schrodinger equation. I've got the equation in the form H(psi) = E(psi) with all the H expanded out, I just don't know how to calculate the energy levels from it. Its probably something I did once know how to do, but...

Homework Statement An experiment is performed on a sample of atoms known to have a ground state of -5.0eV. The gas is illuminated with "white light" (400-700 nm). A spectrometer capable of analyzing radiation in this range is used to measure the radiation. The sample is observed to absorb...

This was prompted by another thread which got me thinking. If CO2 levels are increasing then surely O2 levels must be decreasing? I mean I am just going by basic chemistry, we have hydrocarbons (fossil fuels) where are being burnt and I believe the basic formula is:- Hydrogen and...

I've googled quite a bit. Other than finding articles that require payment to view I have found nothing usable. I need a source - possibly a table would be best - of estimated oxygen levels since the Cambrian. Thanks. - Reason: the only text I have was out of print during the Eocene...

Hello people ! As a CIO, you have been supporting the computing and network services of business applications from 2 centers I and II. Suppose either center is capable of providing all of the service needs, that S1, S2>=0 is the level (quantity) of services delivered from each center and...

hello i have a basic question regarding energy levels of electrons in atoms in bohr's model of the atom. From what I understand if an electron is in an energy level other than the ground state it can either absorb a photon equal to the difference of energy between its energy level and a higher...

The Formula for computing E(n) = -(Z^2)/(n^2) * Ei is fairly straight forward. Am I right in thinking this formula refers to the energy level of the atom with Z number of protons? This formula, what it yields at least, doesn't depend on the number of electrons the atom has? Also, when...

Can someone please help with this problem. I've been looking at it for a week! I can't figure out what equation to use. A si sample with 10^15/cm^3 donors is uniformly optically excited at room temperature such that 10^19 EHPs (Electron Hole Pairs) are generated per second. Find the...

Hello, can someone explain how a line spectrum works. How do they provide evidence of energy levels in atoms? I would have thought that energy levels are to do with a different concept of Bands (Valence, Conduction) so how does a line spectrum provide evidence? :confused:

Can someone please help with this problem. I've been looking at it for a week! I can figure out what equation to use. A si sample with 10^15/cm^3 donors is uniformly optically excited at room temperature such that 10^19 EHPs (Electron Hole Pairs) are generated per second. Find the...

The question states: A system has energy levels uniformly spaced at 3.2x10^-10 J apart. Thepopulations of the energy levels are given by the Boltzmann distribution. What fraction of particles is in the ground state at T=300K. I know that the Boltzmann distribution is: _{}p*j=probability...

1. Are rare Earth magnets harmful to handle and if so what strengths and sizes are safer? 2. Is the magnetic field produced by an electric car strong enough to have harmful effects on a person s health.

Pretty basic question: If energy levels (say, of an electron) are quantized, how is an interaction resolved wherein incoming energy (say, a photon) is not of an appropriate amount of energy to result in an appropriate response (say, moving from 1s to 2s in a simple hydrogen atom)? Suppose the...

Can levels of a protein like NFKappa be lowered to be the same as a younger person's levels? (I mean can either the body be made so that it makes a lower protein level or can the level of protein be reduced after it's been made) I mean because for example people can lower white blood cell...

Does anyone knows how to solve the following eigenvalue equation using matlab? so as to obtain the energy levels in a quantum well structure.. or does anyone has the codes or knows where to find the codes to do so? Eigenvalue equation: tan(sq_root(2mE/hbar^2)*(d/2)) = sq_root((V-E)/E) for...

Does anyone knows how to solve the following eigenvalue equation using matlab? so as to obtain the energy levels in a quantum well structure.. or does anyone has the codes or knows where to find the codes to do so? Eigenvalue equation: tan(sq_root(2mE/hbar^2)*(d/2)) = sq_root((V-E)/E)...

-------------------------------------------------------------------------------- 1. Homework Statement The electrons of a nelectronically-excited neutral magnesium atom have the coniguration 1s^2 2s^2 2p^6 3p 3d. Provide spec notation for the possible quant states of the atom as a whole...

Homework Statement Five electrons (with mass m) whose interaction can be neglected, are in the same 3-dim harmonic oscillatorpotential V(x,y,z) = \frac k2 (x^2 + y^2 + z^2) What is the ground state energy? Homework Equations The Attempt at a Solution I have the energy for the...

I understand that for a semiconductor p-n junction under zero voltage, the Fermi level is constant throughout the junction because that is the condition for a system in thermodynamic equilibrium. I also understand that p-n junction under applied voltage (forward or reverse) is not a system in...

How would you use excitation levels (or the lowest excitation level) to find the radius of a nucleus? And how would it differ to using the r=r0A^(1/3) formula?

Homework Statement Determine the energy levels, their degeneracy and wave functions (in ket notation) of a particle with spin quantum number s =1 if the Hamiltonian is AS_x^2 + AS_y^2 + B S_z^2 where A and B are constants. The Attempt at a Solution' I've spent ages thinking about this...

Homework Statement You have a "U-shaped" container with a valve at the bottom of a negligible volume tube. The left side is filled with water and the right side is filled with mercury. The valve is opened and since the two are immiscible there is a fluid level differentiation. Determine the...

Hi all, It is my understanding that the color of a material results from the inability (or lesser ability) to absorb in that particular wavelength. Reading Atkins' "Physical Chemistry" (8th ed.), I run into a statement I couldn't quite get. On page 730 (chap. 20), he states the following...

Hello all! My professor talked about the quasi fermi levels in my Photonics class. While he did make a good effort, I still am not able to understand the concept. I do plan on going to him on Tuesday to get a clearer idea. But I was wondering if any of you folks could give a general...

Hello Enuma et als. I have a few related questions regarding Prediction Intervals for outliers (individual data points). The basic formula that I use is: Mean +/- T(-1df)*sd*sqrt(1+1/n), where Mean is the sample mean, T is the Z-score from the Student's T Distribution Table minus 1 degree of...

Hi there. It is a fact that, historically, the Schrodinger Equation provides wrong energy levels for the Hydrogen Atom. The same is for The Relativistic Schrodinger Equation (hehe, this is not known by most of students, seek it in arxiv database, it was the original developed by Schrodinger...

A muonium is an atom consisting of a proton and a muon. A muon has the same charge as an electron but about 200x the mass of an electron. Conceptually, how does it make sense that the energy of the first orbit of a muonium is more negative than that of a hydrogen?

Hello, I really need help with this question. Continuum is when the proton/electrons exist in the continuous band of energy levels above the highest bound energy level of the atom. What can be said about the combined energies of the proton and electron is the hydrogen atom is in...

Why the three-levels laser require high energy to start the inversion population? Please answer without mathematical details because I know the solution mathematically, I want the answer physically Thanks

if all the ice sticking out of the water from only the icebergs were to melt, would the water level go up or down?

Some satelites is just hanging there in a geostationary position, like TV satelites, communication satelites etc. Some other satelites are moving around the Earth with a time for rotating around the Earth like something like 2-3 hours (??!) How can this be, some of then is just hanging...

1.in band diagrams, books usually show parabolic bands for the conduction band and the valence band. They will also make note of the acceptor and donor leves in the band gap. However, they always draw straight horizontal lines for these levels. Is that correct? The impurity levels are...

I was wondering how much kinetic energy needs to occur in atom until it emits a photon. For example if you accelerate an atom (like LINAC) what energy and speed is needed for it to emit energy? Or if you heat/vibrate up a copper plate and it starts to glow, what kinetic energy is needed for the...

Homework Statement What does the line spectrum reveal about the energy levels in an atom? The Attempt at a Solution The energy levels are quantized is that right?

Homework Statement If the thermal population of the rotational levels is given by: Nj/No = (2J+1)*exp(-hcBJ(J+1)/kT) Calculate which state has the highest thermal population at a given temperature T. Calculation needs to be shown, not just a result. Homework Equations Nj/No =...

for my question , i will use the term 'level' hey , we know that the zone we live in is made up of atoms (level 0), which are made up of protons, electrons, neutrons , ect (level 1) - for electrons : are there any level 2 known , or nearly found , or theory ? for protons and neutrons we know...

I am looking to calculate the energy gap of for starters periodic elements and were wondering how we could get the list and calculation. Is there a table somewhere based on certain temperatures and constants of energy gap level? We would like to get a list of the energy gap energy for valance...

Hello everybody. As you surely know, the Schodinger treatment of the Hydrogen Atom gives wrong eigenvalues for the Spectrum. The Dirac equation provides for a correct one. On the other hand, the first who found the correct expression for the levels was "mighty" Sommerfeld using a mixture of...

A sample of silicon is doped with indium for which the electron acceptor level is 0.16eV above the top of the valence band. What impurity density would cause the fermi level to coincide with the impurity level at 300K? What fraction of the acceptor levels is then filled? What are the majority...

OK I'm sorry if this may seem like an extremely elementary question, but i just want to get it straight. What are the levels of college education and how long do they take. I know that most basic is associates (2 years) then bachelaurete (4 years & does not require associates degree)...

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Energy levels of a particle in cubic box with sides length a are: E= [(h^2 pi^2)/(2 m a^2)] * (nx^2 + ny^2 + nz^2) where nx, ny, nz are integers 0. If 10 electrons are placed in this box, what is the lowest possible total energy of all the electron? ......... I am finding this...

Homework Statement What values of n are involved in the transition that gives the rise to the emission of a 388-nm photon from hydrogen gas? Homework Equations n=? wavelength = 388nm=3.88x10^-7 m R=1.097x10^7 m^-1 E= hc/ wavelength The Attempt at a Solution E= hc/...