Excitation Definition and 131 Threads

Homework Statement The suspension system of a car traveling on a bumpy road has a stiffness of ##k = 5\times 10^6## N/m and the effective mass of the car on the suspension is ##m = 750## kg. The road bumps can be considered to be periodic half sine waves with period ##\tau##. Determine the...

Hi I am curious to know if quality factor of a resonator depends on the excitation signal or if it stay the same irrespective of the signal applied? Thanks

Can somebody please explain how electron impact can cause optically forbidden transitions in atoms and molecules ?

Does electron excitation for atoms above hydrogen happen at the valence before the core electrons first? I know that for a gamma ray it is due to the excitation within the nucleus, but what about for normal emission spectra. Do we just shine a bunch of different energy onto the atom and...

Hi guys! I have come across a problem I can't seem to wrap my head around. I've learned that E.M. radiation can be propagated by discrete packets of energy , photons. Is the energy of each photon discrete, or can it have a continuous range of energies depending on its frequency? I would be...

I need help with something that i seemed to remember was fairly easy, but just can't seem to find the simple formula for: I have an amount of hydrogen atoms at a temperature of 10000 Kelvin. What percentage of them are ionised and what percentage of them are in the n=2 excited state...

Hello I tried to look for the answer but didn't find enough one for being satisfied How excitation happens in big generators? If we produce electricity from electromagnet on the rotor, and electromagnets need electricity to be activated... and this happens by excitater on same rotor! and this...

Homework Statement (a) Given V, α, κT, μJT, and CP, calculate CV at 90.0 bar and 308 K for carbon dioxide gas. (b) If carbon dioxide's vibrations were fully excited, then CV would be 4R. What's the percent vibrational excitation at 90 bar and 308K? Homework Equations Both constant pressure...

Hi Everyone, I am new to this forums. I am not sure where to post but general discussion is a good place. I am trying to figure out a problem: I have a sample X in gas phase. Say it has an absorption coefficient of 9.895e-18 cm2 molecule-1 @ 532nm. I have a laser pulsed source (say 50 Hz)...

Homework Statement Hello everyone, I have a question from a practice exam I can't seem to figure out. 1. A Ca atom (atomic number = 20) is in the ground state. Light is shined on the atom, exciting the most energetic electron. Which of the following are possible quantum numbers (n,l,m) of...

Homework Statement A nucleus of mass m initially at rest absorbs a gamma ray (photon) and is excited to a higher energy state such that its mass is now 1.01 m. Find the energy of the incoming photon needed to carry out this excitation. Homework Equations m^{2} = E^{2}-P^{2} possibly...

If an electron gets excited from K to L shell, it will actually finish in the 2p subshell and then deexcite to 2s and 1s at the end, right?

Hi, assuming I have the potential for a diatomic molecule in the groundstate i=o and excited state i=1 V_i( r ) = D( 1 − exp[ −β ( r − r_i)] )^2+ C_i Using collisional excitation with fast electrons. What is the vibrational quantum number of the state the molecule will most likely be...

I need help understanding the relationship between the excitation and emission spectra for a fluorescent material. This is not homework. Let's say we have the following graph which plots the two spectra for a given material: Two curves are shown - the excitation spectra and the...

Hi! This is a problem regarding a quarter car model driving over a sinusoidal road excitation. A sinusoidal excitation can be written on the form ze^(jωt), z being vertical. I would like to write the longitudinal excitation of a sine wave on the same form? Any hints and tips are much appreciated.

I've often read that the emission spectrum of a fluorescent molecule is independent of the wavelength used for the excitation. But what happens in the case of a small Stoke's shift where the excitation and emission wavelengths overlap? If I use a narrow band excitation with a wavelength in...

Which mechanism in semiconductors is responsible for electron excitation from valence to conduction band in thermal equilibrium at temperature T? Do valence electrons take their excitation energy from the lattice by absorbing phonon? If so, they can be excited at each arbitrary temperature no...

So I've heard of certain technologies that allow for heating of a certain type of metal inside of the body using external radiation. From what I understand, certain metals can be targeted while avoiding other metals. How does this "selective heating" process work.

Hi all, How can I excitation - ionization solid metal ? May by radioactive material which is too soft.

So.. if you apply a fluctuating magnetic field to an atom at its correct resonance frequency, its pole will go out of alignment of the applied field. How long does it take for the proton/electron to go 90 degrees out of the applied field vs how long it takes to return

Hi everyone, I'm a new member but it's not the first time I look at the forum. Well, I don't know if this is the right section to post my question. I think it is related to quantum mechanics interpretation too. Anyway, let's have a look at my problem. I've computed cross section for photon...

Homework Statement A sodium atom emits a photon with wavelength 818 nm shortly after being struck by an electron. What minimum speed did the electron have before the collision? Homework Equations E_{particle}\geq\Delta E_{atom} The Attempt at a Solution For the minimum energy...

I'm curious, when an electron is bombarded by another electron or photon does the electron even jump at all if the incoming particle does not have the minimum energy to make it jump to the second orbital. That is do the electrons have some sort of knowledge before the collision occurs and know...

How come Higgs Bosons have mass if Higgs field itself gives other thin How come Higgs Bosons have mass if Higgs field itself gives other thing their mass?

Is there any material that can be ionized (plasma state) at realtively low temperature, say 30 or 40C?

I have taken a time dependent fluorescence series of spectra for an ethylene glycol solution using a 532nm laser as the excitation source. I have attached the spectra to this post. Nothing looks unusual-there is a sharp notch near the 532nm line--this is due to a filter I have used to protect...

I have read from time to time (e.g. Lakowicz) that the fluorescence spectrum of a substance is not generally influenced by the wavelength excitation source. On the other had there is a correlation as exemplified in excitation-emission matrix spectra for example. The obvious case is for...

When an electron is excited from a valence band to a conduction band by photons, its velocity changes. Do photons change the velocity or it is another process that changes it?

Homework Statement The diagram simulates a vehicle driving on a rough road. Let v=constant. Find an equation for the response z(t) as well as the force transmitted to the vehicle http://imgur.com/GUQcHx7Homework Equations x'' + 2ζω(x'-x_b') + ω^2(x-x_b) = 0 x_b(t) = X(iω)*e^(iωt) The Attempt...

hi guys, i have a basic question over the atomic excitation and it's relationship with the hydrogen like atoms. we know while excitation the electron in the ground state jump to the higher orbits. but when hydrogen or atoms containing little principal quantum numbered orbits get excited , then...

Hi, I am looking for electronic excitation levels of molecular hydrogen like attached table. but there are only a few electronic states, i need near-threshold energy levels. where can i find all levels? thanks for attention http://imgim.com/5648inciz1637947.jpg

It it being debated whether Electromagnetically Induced Transparency (EIT)/Coherent Population Trapping (CPT) can stop a molecule from gaining an electron. I want now, in this thread, to turn to the possibility of creating transparency/trapping in a molecule that would either suppress...

Hey, Here's the question Now I wanted to check if my thought process was correct and thus my formulation. Some sodium atom is initially excited, emits EM wave with stated λ and then de-excites to the ground state. However, this is Sodium so I think we approximate the energy levels...

Transformer equivalent circuit shows that excitation current is just a tiny friction of the primary current. I always thought the pricinple of transformer was like this: voltage on the primary winding generates the current there, then flux in the core, then voltage on the secondary winding and...

Are SM particles expected to really be i) simple excitations of their associated fields, ii) particulate matter which happens to be very conveniently (and precisely) modeled as excitations of such fields or iii) we can't judge one way or the other in the present state of our knowledge? If they...

I didn't really know how to word this question, but what's confusing me is this: I was researching "what is an electron" and I read in many places that "an electron is an excitation in a magnetic field". But what does this mean? I thought that an electron is just a particle with mass and charge...

Homework Statement Given the relationship Cp/R as a function of Temperature, approximate the number of fully excited vibration modes at a given temperature for a given molecule. 2. The attempt at a solution I have looked through several textbooks and many web sites, but I can't find this...

Hi, i saw these parameter, excitation energy & distribution energy, in structure which have quantum dots with superlattice, and i didn't have any idea about it. can you give me definition or physical explanation about these parameters. Thank you.

Excluding the process of Phosphorescence, an electron in an excited state will return directly or with a intermediate step to its grown state (like in a ruby LASER before the stimulated emission, where first absorbs a green photon, drops to an intermediary energy level and then emits a red...

I have a generator. Single phase 220 volt A.C output Frequency 50 Hz 2000 kVA Rotor winding of my generator was burnt. It was rewinded but it burnt again after 1 day. There are 2 types of windings in stator one main winding which gives 220 volt A.C output and 2nd is excitation winding...

Hello I am new with Maxwell. I made a motor drawing in solidworks and imported it in maxwell. I found some tutorials, and searched on the internet but could not find answer to my problem. So when i try to assign Excitation Current to an coil i get the message Excitation 'Current1' : Cannot...

Hello. I've experiment, which makes plasma using He-1 under atmoshpere & room temp,it's to show how DBD plasma emission energy. As I know that high intensity wave length of He-1 are 588nm,668nm,708nm..etc. If take a formula, ln(a) is propotional to -1/(T-ex). ln(a) is some value.(a has...

Hi people, Time-dependent perturbation theory allows for transitions to excited states, through a sinusoidal perturbation whose frequency is smaller than the energy difference between the states. (That is, P_{a \rightarrow b}=\frac{sin^{2}[(\omega_{0}-\omega)t/2]}{(\omega_{0}-\omega)^2}...

What's happen when a molecule or an atom is already in an excited electronic state and is hit from another photon? Example 1: my molecule absorbs a VIS photon (there's a time in which the molecule is an upper electronic state before the re-emission or etc. etc. process) what happen if another...

Hi everyone, Im looking to measure the resistance of a 3-wire RTD using a basic data acquisition system and LabVIEW. My DAQ "box" doesn't have any internal excitation sources, and I realize one is necessary to measure resistance across the RTD element. I'm unsure as to how to construct am...

Hi guys, I will really appreciate it if you respond to this my question. Actually I am working on a linear generator that can be use on land to generate electricity from the movement of vehicles. The system consists of a magnet that is connected to a spring as shown in the picture. The...

As I studied, the optical branch of a crystal is called so because it can be excited with e.m. fields but I wondered whether it is possible to excite the optical branch also with chargeless particles like neutrons or the charge/action-on-charge is necessary for the process? And if so, why? I...

I have drawn up what I believe happens during electron excitation in an atom. However, it looks very... wrong somehow. My diagram shows an elestron moving in time but not space until it is hit by a photon, after which it disappears and instantly reappears at a higher energy level. After some...

where can I get information about the excitation levels (gamma ray spectrum) of a single proton nucleus?

Hey, Can someone point me in the direction (or just explain to me!) the idea of Anode Break excitation in neuroscience ? Thanks