Homework Assignment #9
Interference of Light Waves
What you will learn from this
section
- how Thomas Young demonstrated the wave
nature of light two hundred years ago
- how to predict the positions of bright
fringes in a two-slit pattern displayed on a screen
- what a diffraction grating is and why it's
useful
- optics vocabulary for this
section:
- fringe
- order
- diffraction grating
How to approach this material
- Read section 4, Wave Optics, from pages
68-72 (part of this you read last time; this time, look at the
equations!)
- Read the supplemental material in this
folder
- Visit these web sites for more information.
BE SURE TO TRY THE TWO-SLIT APPLETS, since you won't be doing the
actual experiment
APPLETS:
You can try a "home" two slit experiment,
but it's not easy to get it to work. The way it was done by poorly
funded schools in the "old days" was to create two slits by
blackening a piece of glass (microscope slide) over a candle flame
and scratching two closely spaced lines (they need to be less than
about 100 microns apart) with razor blades. I recall that we held
two razor blades together (there was still a slight air gap
between them) and quickly made the double scratch in the soot.
Shine a laser pointer through the two slits and project the
pattern on a wall.
- Do the homework problems in this
folder.
If you have questions
- Send an email to Judy
jdonnelly@trcc.commnet.edu or to Randy
rseebeck@trcc.commnet.edu
- Post a question in the discussion
forum
- Talk with a mentor, or another student (we
learn best when we help each other!)
- Stop by the Virtual Classroom during posted
office hours
When you are finished
- Fax (860 886-5063) or email your homework
to me by the due date. (see the assignment folder) If you fax, be
sure to write "ATTN: JUDY DONNELLY" on the first page, and to
number the pages.
- Check the calendar for the due date for the
lab.