Absorption Definition and 534 Threads

I've been looking everywhere for information on the absorption spectra of molecular hydrogen. I need some pretty exact numbers. If anybody can point me in the right direction it would be greatly appreciated.

What is “undamped vibration absorption” ? What is “undamped vibration absorption” and how would you use this concept to absorb the vibration of a un-damped, simple mass spring system of mass m and stiffness k oscillating at its resonance frequency?

Lets take this specific example: Sun is radiating heat and a water tank with a certain surface area S absorbs this heat. Sun rays are perpendicular to this tank. [PLAIN]http://pokit.etf.ba/get/778c2978a453178481d142a891ae07c5.jpg If I know much energy did my tank of water...

so just about finishing a report on x ray abosprtion on different materials, generally the linear attneuation coefficent increases with atominc number Z. However silver(47) had a lower attenuation coefficent then zirconium(40) despite having the significantly higher value of Z. With some...

so just about finishing a report on x ray abosprtion on different materials, generally the linear attneuation coefficent increases with atominc number Z. However silver(47) had a lower attenuation coefficent then zirconium(40) despite having the significantly higher value of Z. With some...

Hello! I’ve recently become very interested in Sorbothane as a shock absorbing material, with the purpose of protecting sensitive equipment of mine from drops. My background on physics is limited and I would really appreciate any help, especially since Sorbothane can be costly and I’m a...

Hi all, Physics was never my strong point at school, yet here I am looking at the differences between three types of graduated light filter for a Health Sciences Masters degree. I'm in the process of writing up, and one of my sets of results is a bit bewildering. Basically, I measured the...

Homework Statement Complete this sentence. When doing Bragg scattering of x-rays off of NaCl, the first order K-Alpha peak has an energy that is ___________ the energy of the second order K-Alpha peak. Known Information It is known that the Intensity of the K-Alpha is greater than the K-Beta...

Hi, could someone tell me how the fine edge structure next the the absorbing edge in an XAS arises? from my understanding an XAS is a plot of absorption coefficient against energy of incoming xray. The absorption edge is at an energy corresponding to when the energy is just sufficient to...

Homework Statement A Mixture of air and acetone is being vented from a solvent recovery plant. The air has to be scrubbed and this is done by absorbing the acetone into water in an absorption column. The acetone is present in small amounts and its concentration never rises above 4 mol % of the...

Hello all. I'm am a first time poster but a long time visitor. I am having a little trouble that I was hoping someone far wiser and more knowledgeable than myself might be able to help with. I've been using MCNP to investigate criticality in a simple geometry consisting of a central natural...

I'm confused about infrared spectroscopy. Wikipedia states that "when the frequency of the IR is the same as the vibrational frequency of a bond, absorption occurs." However, if I look at some vibrational transitions of HCl for the anharmonic oscillator, I see: 0-->1 \omega = 2885.7...

Hey, It seems like this is impossible because momentum conservation is violated. I had a Q where an electron underwent an energy transition and emitted a photon, and then they asked whether it was possible for the photon to be reabsorbed by the electron to undergo the same transition as...

Looking at a HCl spectrum (from hyerphysics: http://hyperphysics.phy-astr.gsu.edu/hbase/molecule/vibrot.html), I don't understand why there is a gap in the middle of the spectrum that seems to act as a line of symmetry in the x-axis. Can anyone help please?

Homework Statement 1. When an aircraft flies above the clouds during the daylight period it is continuously exposed to sunlight. This sunlight heats up the cabin. Although the outside air temperature at cruise altitude is – 56 degrees this is still one of the determining factors for the sizing...

hi, this might be the wronge place to post this but trying to find this info on the web is exceedingly dificult. I need a material that is cheap has a heat insulating effect and has high transparency and permeability for al forms of the light spec rum including uv and infared. That is part...

Homework Statement A sphere of radius 0.500 m, temperature 27.0°C, and emissivity 0.850 is located in an environment of temperature 77.0°C. At what rate does the sphere (a) emit and (b) absorb thermal radiation? (c) What is the sphere's net rate of energy exchange?Homework Equations...

Hi, i am doing a project course in masters. i need help regarding on X-ray Spectrum absorption by semiconductors. I am doing the simulations in XOP(X-ray oriented programs) software which is freeware at http://www.esrf.eu/UsersAndScience/Experiments/TBS/SciSoft/xop2.3 . So, my doubt is...

Homework Statement A silicon wafer that is 200 um thick has no front reflection, 30% back reflection and absorption coefficient \alpha=39.9 cm^{-1}. What is the flux absorbed? Homework Equations Beer's absoorption law: \Phi(x) = \Phi_0 e^{-\alpha x} The Attempt at a Solution...

When white radiation is passed through a sample of hydrogen gas(atoms assumed actually) why are absorption lines observed in Lyman series only? The corresponding photon energy range for visible light(380-780nm) are 1.59-3.27eV which should cause transitions of electrons in the first excited...

Hey I recently did an experiment on the absorption of gamma rays I calculated the thickness and the no. of counts, got a nice exponential curve. So, I used lead as the absorbent or shielding material for gamma... Any suggestions what else I can use for gamma? I thought about sausages or...

Hi there! I have a question about the classical interaction of light with matter according the Drude-Lorentz model. Let's suppose that the light in matter has a wave-number k which in general is complex. Then the real part of k accounts for the propagation of light, while the imaginary part of...

I am studying on the electrical properties of organic compounds and having a problem with photoinduced absorption spectroscopy applied to these materials. Because in all the books, articles, etc , information given is on the results of applying this method. However i need to learn what PIA...

Homework Statement Just basically want to see if my algebra is ok. Homework Equations All are relevent. The Attempt at a Solution Calculating Rates in Magnetic Moments to Predict Period Interaction Between a Fermion and the Zero-Point Field First we must identify the net...

I'm looking in a textbook at a discussion of a semiconductor quantum well which is being irradiated and an absorption spectrum produced. Electrons are being promoted across the band gap and holes are being created. There are heavy hole and light hole transitions, and the spectrum shown rises in...

Homework Statement Consider the following random walk on the integers: \mathbb{S}=\{0, 1, 2, 3, ... , L\} Let Wn = {the state k \in\mathbb{S} you are in after the n'th transition} \mathbb{P}[W_{n+1}= k \pm 1 | W_{n} = k] = \frac{1}_{2} For \ 1\leq k\leq L-1 Otherwise...

Homework Statement 1.if you were to paint a house that reflects heat during summer and radiates heat during winter nights. which color should a house be painted? green, red, black, white, or pink? 2. why do gardeners mix soot in the soil? The Attempt at a Solution 1.i say it is...

Is there difference in absorption rate between various berries and fruits due to a place where you and your ancestors have lived? What I meant, is it true that my organism will absorb vitamin C much better from black currant than from lemon or kiwi (because I live in Baltic states and black...

Consider a slab of matter contained within two infinite planes a distance of s = 1m apart. absorption coefficent =1m2kg-1 density of slab 1kgm-3 heat capacity 103^3jk-1kg-1 assume the absorption coefficient to be independent of wave length 1.Suppose one face of a slab is illuminated...

Hi,I need help with this question Assume you have a laser emitting a wavelength of 800 nm with power 20 W. You irradiate a goblet filled with water whose layer is 0.25 cm thick. The absorption coefficient of water at this wavelength is 0.65 cm-1. a) What is the remaining power behind the...

I'm sure I'm overlooking something simple here. I am trying to understand characteristic x-rays given off during photoelectric absorption of a photon. The energy from the photon is given to an inner orbital electron and the photon no longer exists. The electron uses the energy to escape, and...

I have been recently trying to advance my understanding of thermodynamics, but i have encountered a problem when it comes to absorption heat pumps and similar systems. The standard heat pump requires an energy input, to move heat energy from one location to another. Most would consider...

Homework Statement I am currently doing a biology honours project at university and have been stumped by a fairly basic physics hurdle. I need to know the equation to calculate the amount of light absorbed by water/unit depth. I have tried to find the equation all over but cannot find...

I have been wondering how to realize the color of a mineral by having the absorption Spectra... The following case is an example; The image is the absorption spectra of a Bolivian Amethyst which looks like this; [PLAIN]http://www.tequilabay.com/amethyst300lbbolivian.jpg I have tried...

Homework Statement The antimalarial drug quinine has pka = 8.4; is it likely to be absorbed by passive diffusion through lipid membranes in the stomach (ph = 0.9) or ileum (ph \approx 8)? Why? Homework Equations n/a The Attempt at a Solution If the pH of the environment is...

This is probably a really basic question, but I realized I'm not sure what the answer is. What is the mechanism for light heating an object? Are photons always absorbed by electrons (if they are absorbed at all)? Maybe this will help explain my question: People often say that infrared light...

This thread is related to another question that I have been pondering. In most objects that we experience on a daily basis (a green shirt for example), we know that most of the frequencies of light striking the object are absorbed. I simply can't believe that the atoms in the shirt have...

Linearly polarized light does not carry angular momentum. However, individual photons emitted, say, in the direction of the X-axis, carries a spin angular momentum \hbar in the direction + X or -X. And, when absorbing of the photon, target gets its energy h\nu and its angular momentum \hbar. Is...

what is the practical use of the concept of band gap other than classification between material? can free carrier absorption be manipulated by changing band gaps?

Hi I'm self-teaching calculus and I'm looking at exponential growth and decay. The differential equation for relationships like these if this was related to time is dP/dt = -kP i.e. the rate of change in P with time decreases at a rate which is proportional to the amount of P present. I can...

I have a very basics question. I have a question about absorption in molecular bands. When looking at spectra in the infrared region and comparing it with simulated spectra, I can see that some lines get partially absorbed and then grows to fully absorbed in the "center" of the absorption...

The diagram (see attached) represents some of the energy levels for an atom of a gas. White light passes through the gas and absorption lines are observed in the spectrum. Which electron transition produces the absorption line corresponding to the lowest frequency; A. E3 to E2 B. E2 to E3 C...

My textbook says "absorption yields color. emission yields fluorescence" - can someone explain what that means exactly. I know color is when something absorbs all wavelengths except one, which gets reflected and produces color. If it helps... the chapter is on bohr's model.

Homework Statement A naked person, whose skin area is 1.7 m2, sits in a sauna that has a wall temperature of 61oC. If the person’s skin temperature is 37oC, find the net rate at which the person absorbs heat by radiative transfer (assume an emissivity e of 1). How much liquid must the...

An isotropic solid has a refractive index of 10 at low frequencies. A 10 um thick platelet of this solid with perfectly polished planes shows two absorption bands in optical transmission. These bands, corrected for reflection, have a (negative) Gaussian shape. They occur at frequencies of 3x1012...

Why do the chlorophyll in land plants absorb primarily in the blue and red wavelengths, http://en.wikipedia.org/wiki/File:Solar_Spectrum.png" ? Isn't more energy available in 500nm green light vs 700nm red light? E =\frac{hc}{\lambda}

Hi, I'm trying to find out the total number of solar neutrinos that interact with the human body per second or per lifetime. I know we are exposed to many, most which pass straight through us, but I'm interested to know how neutrinos interact with matter. Thanks.

I have several electronic spectra for different cobalt complexes which I need to analyse. I am fine with finding \lambdamax and the molar absorption coefficient etc. However it also asks me to mark absorption bands on the printout and tabulate \lambdamax values and absorbance values for these...

Hello, I am currently creating a program that calculates the change in observed intensity (nadir) from initial intensity within the atmosphere. As I am studying particular compounds, a first suggestion for my work is to produce a 'forward model' based on very simplistic radiative transfer...

Hi readers, I'm confused about some aspects of absorption spectroscopy, and hoping someone can de-confuse me First, just a preliminary question; am I right in thinking that when an electron absorbs a photon, the electron will then emit a photon of the same frequency and energy as the one...