# Possible frequencies of an electron

• Dec 13th 2010, 06:35 PM
gbenguse78
Possible frequencies of an electron
Hi
Could someone kindly clarify the following?
1. The problem statement, all variables and given/known data
In its ground state the atom absorbs 2.3 × 10–19J of energy from a collision with an electron.
(i) Calculate all the possible frequencies of radiation that the atom may subsequently emit.

2. Relevant equations
E=hf

3. The attempt at a solution
Using h as the planck constant and E being given , I obtained a frequency of 3.5 x 10^14 Hz.
But how do I determine the possible frequencies?
Highly appreciate any suggestions.
• Dec 14th 2010, 12:24 AM
chisigma
Quote:

Originally Posted by gbenguse78
Hi
Could someone kindly clarify the following?
1. The problem statement, all variables and given/known data
In its ground state the atom absorbs 2.3 × 10–19J of energy from a collision with an electron.
(i) Calculate all the possible frequencies of radiation that the atom may subsequently emit.

2. Relevant equations
E=hf

3. The attempt at a solution
Using h as the planck constant and E being given , I obtained a frequency of 3.5 x 10^14 Hz.
But how do I determine the possible frequencies?
Highly appreciate any suggestions.

The energy of the emitted photon cannot exceed the collision energy, so that the frequency $\nu$ of the emitted photon will be $< 3.5\ 10^{14}$ Hz...

http://digilander.libero.it/luposaba...ato&#91;1].jpg

Merry Christmas from Italy

$\chi$ $\sigma$
• Dec 14th 2010, 01:09 AM
gbenguse78
So will any frequencies less than 3.5 suffice? The answers were 0.3 and 3.2.
• Dec 14th 2010, 04:57 AM
chisigma
After the collision the electron will jump from a quantum state to another quantum state with greater energy, so that the energy badged requires that...

$\displaystyle E_{c} = \Delta E + h\ \nu$ (1)

... where $E_{c}$ is the collision energy, $\Delta E$ the energy gap between the initial and final state and $\nu$ the frequency of the emmitted photon. In order to answer Your question one has to know the possible quantum state of the electron...

http://digilander.libero.it/luposaba...ato&#91;1].jpg

Merry Christmas from Italy

$\chi$ $\sigma$