Photon emission Definition and 70 Threads

I'm sure I've heard the explanation for this before in class but I can't quite remember it: If electrons of an atom emit photons (ie lose energy), the orbits of the electrons will become smaller, right? If so, wouldn't the atom eventually collapse? What radially outward force keeps the...

Homework Statement A light bulb 10km away from you emits visible photons at a rate of 3x1018 photons/s. Assuming this is the only source of light (the whole place is dark), and your dark-adjusted retina has a diameter of 7mm, then how many photons/s hits your retina? Homework Equations...

On the web are some informed-sounding discussions saying that the various videos showing the appearance of the dots on the photo-sensitive surfaces can by no means guarantee that only one photon got through. A lot hinges on that, thanks for referring me to other posts which show certainty of a...

I've looked at a few introductory treatments of the quantum harmonic oscillator and they all show how one arrives at the discrete energy values E_n = ( \frac {1}{2} + n ) hf \hspace {10 mm} n=0,1,2... usually by setting up and then solving the Schrodinger equation for the system...

Homework Statement When a hydrogen atom undergoes a transition from the n=2 state to the n=1 level, a photon with \lambda=122nm is emitted. a)If the atom is modeled as an electron in a one-dimensional box, what is the width of the box in order for the n=2 to n=1 transition to correspond...

Homework Statement Show that the fractional change in frequency of a photon absorbed or emitted by an atom initially at rest is \frac{\nu - \nu_o}{\nu} = \pm \frac{h\nu}{2Mc^{2}} where M is the mass of the atom, \nu_o is the frequency of the transition uncorrected for the recoil of the atom. In...

Let's say we just had a normal atom in energy state E, and one of the electrons jumps down to a lower orbital E'. Of course, E - E' is positive because E' is a lower orbital than E, so the energy of the photon emitted must be positive. But what if E' were a higher orbital than E? Could the...

Based on the following excerpt, I'd appreciate any general comments/observations and then follow with a specific question. Leonard Susskind says in THE BLACK HOLE WAR, 2008, PG 347 : #: my parenthetical comment I knew physics was crazy, but that just seems "over the horizon" crazy...

k my physics background is limited , I know that photon emission is when the electron moves down in energy level thus releasing a photon but how does the photon get inside the electron , the energy that moves the electron into a higher level when this energy moves the electron out their...

Classically, I think it is correct to say that Maxwell implies an accelerated electron will "radiate" What is the quantum take on this please? In particular, what determines the wavelength of the emitted photon? PS I may ahve asked something like this before, but I never found an answer...

Can someone tell me about photon emission? If an electron bound to a nucleus emits a photon and drops to a lower energy level, in what direction does the photon go? - Does it leave the electron perpendicular to the tangent line of the electon's 'orbit' at the instant of emission - that is...

I've been obsessed with the derivation in the attachment for hours now, all rights & credits to the one who came up with it, but I completely can't follow it. How does one get rid of the e's and epsilons?! How to combine the momentum and energy equations? Squaring gives for me just onworkable...

What happens when a single atom emits a single photon? Does the photon itself exist as a spherical wavefront that propagates in all directions? Or is it ejected as a tiny, "vibrating ball"? In other words, is the spherical wavefront of a light source (like a star) just the result of the...

Homework Statement The problem involves an atom (Said to be in an excited state of energy Q_0) traveling towards a scintillation counter with speed v. The atom then emits a photon of energy Q and stops completely. The rest mass of the atom is m. I'm supposed to show that Q =...

Hi. This isn't so much a homework question, but more of a conceptual understanding question. Lets say an atom has a ground energy level defined at 0J. The energy levels are: E1 = 0 J E2 = 7.77*10^-19 J E3 = 10.66*10^-19 J E4 = 14.1*10^-19 J E5 = 16.6*10^-19 J Now, if an electron...

I’m having some trouble with a question from my special relativity assignment. It relates to the frequency of a photon emitted from an atom which then subsequently recoils. The atom has initial rest mass m0, and loses rest energy ‘e’ in the emission (“e is the difference between the rest...

When a photon is emitted, where did it come from? Did something cause it to be created and then emitted, or was it inside something and then released? How's it work?

I'm really lost on these 3 questions. My physics teacher decided she was sick of thermodynamics and gave us this packet over material we haven't covered yet, but she expects us to get it without any problem. I'm really stuck on these: 1. Assume that sodium produces monochromatic light with a...

when an excited electron emits a photon what happens to the EM field of the electron

Classically, a pulse of light emitted by an atom would be viewed as an electromagnetic wave radiating spherically symmetrically out from the atom. Quantum mechanically speaking, if say a hydrogen atom emits a single photon, does the photon's wavefunction spread out spherically, us having no idea...