Compute Wavelength of Electron Moving at Various Speeds

[s3b4k]

Homework Statement

1. A photon is emmited when an electron confinded to a box of length 10^-9 m undergoes energy level transition, and has a frequency of 2.50 x 10^15 Hz. Find the energy levels associated with emited radiation

Homework Equations

E=n^2h^2/8mL^2
E=Hc/wavelength
E= -13.61/n^2

The Attempt at a Solution

i have no clue

Homework Statement

compute the wavelength of an electron having speed a) 3 x 10^4 m/s b)0.1 x speed of light

Homework Equations

E=n^2h^2/8mL^2
E=Hc/wavelength
E= -13.61/n^2

The Attempt at a Solution

not sure

Homework Statement

A hydrogen discharge tube(lamp) is excited with energy 13.15 eV. How many possible lines would be obsererved in the emission spectrum of these atoms as a result of this exciation, and which ones would be visible. Visible range 4000A and 8000A

Homework Equations

E=n^2h^2/8mL^2
E=Hc/wavelength
E= -13.61/n^2

The Attempt at a Solution

something with factorial not sure how to though

 

[buffordboy23]

Homework Statement

1. A photon is emmited when an electron confinded to a box of length 10^-9 m undergoes energy level transition, and has a frequency of 2.50 x 10^15 Hz. Find the energy levels associated with emited radiation

Initially, the electron is in some unknown stationary state. Then the electron emits a photon of "specific" energy and is now in a lower state. What is special about the energies associated with the different stationary states? They are quantized:

$$E_{n} = \frac{n^{2}\pi^{2}\hbar^{2}}{2mL^{2}}$$

Do you got it now? By the way, where did the 8 come from in your formula?

 

[s3b4k]

im not sure its in my formula book, where did you get the pie from i don't have that in the equation

 

[malawi_glenn]

He is using h-bar.

$$\hbar = h/(2\pi )$$

And you have all the equations you need for this, why don't you make a serious attempt to solve it?
If you have NO clue, make a (motivated) guess!

 

[malawi_glenn]

Initially, the electron is in some unknown stationary state. Then the electron emits a photon of "specific" energy and is now in a lower state. What is special about the energies associated with the different stationary states? They are quantized:

$$E_{n} = \frac{n^{2}\pi^{2}\hbar^{2}}{2mL^{2}}$$

Do you got it now? By the way, where did the 8 come from in your formula?

He is using equation with h, placks constat, you are using formula with h-bar. Be careful! :-)