Transition between high energy level to low energy level?

Question

how do i work out the energy of the photon and how would i know what electromagnetic spectrum the photon would lie in

Answer 1

Hello Summer-

Here is a reference which will probably answer most of your questions...

http://library.thinkquest.org/19662/high...

-Fred

Answer 2

The energy of a photon is given by Einstein's (photoelectric effect) equation, namely: -

E = hf

Where 'E' is the photon's energy, 'h' is Planck's constant, and 'f' is the frequency of the photon. Thus, if an electron (atomic model) decays from a higher energy level E(h) to a lower energy level E(l) then the energy 'E' of the emitted photon is: -

E = E(h) - E(l)

And so the frequency of the photon is: -

f = E/h = (E(h) - E(l))/h

Hence, to find the location of his emitted photon within the electromagnetic spectrum (EM for short) - use the following link: -

http://en.wikipedia.org/wiki/Electromagn...

and the table of EM frequencies to identify which part of the EM spectrum the photon occupies.

  

Answer 3

Take the value of the high energy level, and subtract the value of the lowe evergy level.  This will give you a figure which should be in eV, or Electron Volts - convert this to Joules by multiplying the eV figure by the charge on the electron (1.6e*10e-19)  This difference will equal the energy of the emitted photon.

Use that figure in the equation E= hf, where:

E is the energy in Joules

h is Plancks constant (6.626*10e-34)

f is the frequency of the photon in Hz

You'll already have the E and h, all that's left to find is f, the frequency.

Then put that figure into the equation v= fw, where:

v is the velocity of light (3*10e+8 m/s)

f is the frequency (in Hz) you just got from the first equation

w is the wavelength of the light.

Once you have the wavelength, mark it roughly on an electromagnetic spectrum found in (I hope) all good physics textbooks, this will show you the part (and perhaps even the colour) of the emitted light, the photon.