This was our last regular physics class of the year, though a few of the students are taking the SAT Physics subject test next month so we’re going to meet a few more times to review for the test.  The last chapter of Light & Matter is about Bohr’s model of the atom.  There are some excellent youtube videos on the subject, and I basically made my lecture notes watching Doc Schuster’s videos.  If you’re trying to learn physics on your own I think you would fair pretty well just watching his videos.  He’s very entertaining.

And Paul Andersen at Bozeman Science has a nice video on this topic as well.

Since I don’t have a spectrometer, we couldn’t do the usual spectrometer lab to look at the Balmer lines of hydrogen, so I cheated and gave each of the students a photo of the spectrum to use as their ‘data’.

Hydrogen

I found this lab online and basically just used the first page.  I had the students find the first 6 energy levels for a hydrogen atom and draw the energy level diagram. Then they used the wavelengths above for the Balmer series to determine the ionization energy, or ground state energy level of hydrogen.  This involved using a spread sheet to make some calculations and plot the data, find the slope and from that we found the energy of the ground state to be 13.7 eV very close to the accepted value of 13.6 eV.  This lab was more an excercise on using spreadsheets and finding slope than actual lab work but I still think its useful.

 

Advertisements