Discussion in 'General Discussion' started by SoSolid, 21 May 2006.
Is an X ray photon an electron?
no, its still a photon, a light particle.
But aren't X rays electrons that have lost energy and the release of energy is the x ray?
X-rays are photons generated by firing electrons at metal.
The release of electromagnetic energy is the x ray. This is a photon. Photons and electrons are two different particales, aand as you yourself asked if an X ray photon is an electron.
A bit more info can be found there.
It's just that I am stuck on an A level physics question which gives me the energy of an x ray photon and asks me to calculate the speed of it. I was thinking if an x ray was an electron I could use e=mc^2 I can't think of any other way to work out the speed without knowing its wavelength or frequency?
It's a photon so its speed=c
an x-ray photon would just just be a photon with a wavelength of what... 10^-9 - 10^-10
you can calculate the frequency of them using f=c/λ
not sure why you are being asked to work out the speed.. its a constant
then just use e=hf to find the energy
or just e=hc/λ
an x-ray is just a photon with a specific wavelength
just like radio waves are.. and visible light etc...
edit: convenient: http://www.lbl.gov/MicroWorlds/ALSTool/EMSpec/EMSpec2.html
check your answer against that (its in eV though, so don't forget to divide by 1.6x10^-19)
You know E = hf = hc/(lambda) so you can work out the frequency.
The de Broglie wavelength is (lambda) = h / p
So, hc/E = h/p, i.e. p = E/c.
Although being a photon, it's speed is c. You sure its asking to work out speed?
it has no m, it's a photon
ah, ninja edit
actually, quite a few A level physics questions will be these sort of trick questions for one or two marks.
Check the question again.
speed, not energy. thats what he needs to find, apparently.
under most circumstances, the speed will be 3x10^8. I can't see that being the question
perhaps its something to do with the photoelectric effect, difficult to tell from the OPs wording
As someone who took A level physics only a year ago, I can attest to the fact that they do have these little trick questions.
hence why I suggested it being one.
Not quite. The method of creation has no bearing on the nature of the reulstant photon. X-Rays can also be created in inter-stellar collisions, for example, as measured by CHANDRA.
To anser the OP, an X-Ray photon is simply a high energy photon.
It may be questioning what the recoil velocity is - an atom of mass m emits a photon with energy E, at what speed does the atom recoil....that kind of question.
come on OP, tell us the whole question!
Its a photon isn't it, oh and has anyone seen that X-Ray lazer majig?
I know it has no bearing on the resultant photon. However, what we define as X-rays and gamma rays overlap, the only difference being the method of creation.
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