YOUR LABORATORY REPORT:
Your Lab report should be generated in a word processor of choice. Bear in mind that
your TAs are limited to reading *.doc, *.docx and other files readable by Microsoft
Word. Below you will discover our general expectations as to Format and required
content of your Lab Report. We encourage you to be thoughtful and creative in your
presentation of the requested information. There is no one way to convey information.
Please take the time to consider possibilities for presenting a complete Report that is easy
to read and follow.
1. A COVER PAGE with the following information: experiment name, your name, your
partner’s name (so designated as partner), conference number, conference instructor’s
name, date of lab, and due date for the report.
2. TABLES I and II of measured and calculated quantities in a neat final form, complete
with titles, column labels, and units. List your station number, and grating constant
directly under Table I. (List for EACH week, if different.)
3. DATA SETS of angular DIFFERENCES from which you chose the  for hydrogen
and the  for mercury/mystery measurements.
4. SAMPLE CALCULATIONS of “Measured ”, “Observed Relative Error”, and
“Predicted Relative Error” for one of the Hg spectral lines. Be sure to show each
formula in symbolic form, then the same formula with numerical results with units.
5. CALCULATION of “Measured ” for the mystery spectral line and of the
uncertainty  in that wavelength value. Obtain  from the “Predicted Relative
Error”, which is By using the CRC, found in the Physics Library, and some
“methodology” determine which of the Noble gasses you have worked with in the
Lab
6. Given that to first order:
 = (1/s)106 sin 
(m = 1, s in lines/mm,  in nm),
show by the use of calculus that the worst-case “Predicted Relative Error” – the
fractional uncertainty ||/ is:



s
s

cos 

sin 
Explain your handling of signs and absolute values; explain why this is worst-case
(i.e., cannot get any larger than this). Also, write a sentence or two to explain in
words the meaning of this equation.
7. DISCUSSION and CONCLUSIONS
a) Comment on the comparison between the “Observed Relative Error” and the
“Predicted Relative Error” for the several H and Hg spectral lines. If your values
for  seem to be appropriate, much too large, or too small? If much too large or
too small, explain how the situation might be improved.
b) State the measured value of the unknown wavelength, complete with uncertainty,
in the form   (example: 500 ± 2 nm). By this statement you are going on
record as predicting that the unknown wavelength most probably lies in the range
 –  to  + . Based on your examination of the H and Hg results, do you
believe this prediction to be correct? Why or why not? Based on your H and Hg
results, what better value, if any, would you prefer for ? Why? Your objective
here is to estimate the smallest uncertainty that leads to a wavelength range that
almost surely brackets the true value of the unknown wavelength.
c) What is your unknown Noble Gas?
YOUR GRADE ON THIS REPORT WILL BE BASED SPECIFICALLY ON THE ITEMS
LISTED ABOVE AND THE DEGREE TO WHICH YOU ARE SUCCESSFUL IN WORKING
WITH AND INTERPRETING YOUR OWN RESULTS IN A SELF-CONSISTENT FASHION.