Recent content by tyneoh

Right, how about an atom absorbing the excitation energy it needs from an incoming blue photon, and the photon leaves with the remainder of its original energy, except now that it has a lower frequency, say red?

Then does the theory disallow the possibility of absorbing a portion the energy of an of an incoming say, violet photon and and render the photon into say, a green photon whose frequency corresponds to that of the remainder energy

Hi Guys! I have a confusion which I hope you can help clear up. The mathematical expression of the first law of thermodynamics can be stated as δu=Q+W where u is the internal energy of the system, Q is the heat added(or taken from) to the system and W is the work done by or on the system. If I...

OK so just to clarify, the quantum theory explains that radiation is carried by discrete packets of energy (photons) whose energy must also be discrete? Would that mean orange light from a sodium lamp cannot be changed in any way into other colours by altering the frequency of the "orange" photons?

Isn't the energy of a photon continuous, since its frequency can take on any value?

What if the frequency of the photon decreases to the corresponding amount of the remainder energy? i.e. the frequency of the photon decreases after some of its energy is absorbed by the atom.

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...

Okay I am starting to see the gist of it, but could you care to explain why harmonics are required for solid boundaries but not for open-ended conditions? Do sound waves in a pipe count as open-ended or bounded?

I am a little bit confused though, do standing waves form at all frequencies as long as you have two waves of similar amplitude and frequency traveling in opposite directions? For resonance only then you need harmonics?

Also, are standing waves examples of resonance?

So to answer my question, standing waves on a string attached to a fixed point do not require harmonics whereas standing waves between two speakers do?

For transverse waves on a spring, doesn't the applied frequency have to be one of the harmonics to form standing waves? By boundary conditions, I assume those are the variables in the fundamental frequency formula?

If so then standing waves are just resonance in work?

Do all frequencies produce standing waves or just the harmonics? My physics textbook stated that standing waves are form when two wave trains with equal amplitude and frequency meet each other in opposite directions. Does the common frequency of the wave trains have to be one of the harmonics...

Homework Statement Let v1, v2, v3 be a sequence and let un=nvn-(n+1)vn+1 for n= 1,2,3... find \sumun from n=1 to N. Homework Equations The Attempt at a Solution Began with method of differences and arrived at Sn= v1-(n+1)vn+1