Week 6

Feb 10

Michelson
• Intro Feb. 10
• Data done Feb. 17 th
• Analysis Due Feb 19 th
• Final due Feb 26 t

Write out project ideas for HW (Due Wed Feb 12). Note that we keep coming up with evolving ideas (acoustic standing waves, holography). If you have ideas regarding equipment/space needs---now is the time

• At the end of the course you will present your work as either a poster or short ppt (I'll decide--it is not an option).---but the class can discuss.
• If equipment needs to be purchased (holography kit for example)--then that needs to be done ASAP.

We'll discuss Michelson Interferometer Monday.

Tues, Wed--lets plan on meeting briefly. We start peer reviews.

I'll likely get papers back to you Tuesday (I've made a pass).

Comments on Schawlow write ups.

• I am seeing much discussion using the word "not" to describe what was not done. Instead describe what you DO. There is no NOT, there is only do or do not.
• Make sure you tell me how you obtain results (small angle--not permitted, average of two measurements and how you average, weighted uncertainties on fitting, etc).
• There is a difference between "wiggly line equals" and "equals". When you make an approximation, one of these things does not belong.
• Overall I am seeing great work, good thoughts, good writing.

Michelson: Your tasks will ultimately be to 1) determine wavelength of HeNe by laboriously counting (or not), 2) determining the separation of the two sodium D line wavelengths (well known---you shall get a high precision number--we'll check later). 3) Determine the precise position for the mirror to obtain white light fringes. 3) will be your "one on one".

Notes: In order to get good white light fringes, you must run through good careful alignment of HeNe laser friniges and get close to ZPD (zero path diff). I will say with some pride I obtained better/faster fringes on all three set ups the other day. I still am not so cocky that I will leave it to chance and set it up in front of you. I left it set up on white light, I'll work backwards to sodium washouts, then laser. Takeaway message---I am uncertain I can get good white light fringes while you watch in 5 to 10 minutes of class time. During one on one--you'll have thirty minutes---after properly messing up the entire alignment. Practice. Practice. Practice.