Physics Lab Report Formats
Chabot College  

Writing Physics Lab Reports.  This is a concise discussion of what is expected in a lab reports for  Chabot's  Physics courses. It follows closely protocols laid out here: http://www.physics.upenn.edu/~uglabs/  , page 5  of the Lab Manual  (All Courses.). You will generally receive additional information in class. Visit

http://library.thinkquest.org/10796/ch1/ch1.htm

and review rules on sig. figs with respect to multiplication ,  division, addition and subtraction, which are important for the lab
write ups. The lab report, other than  data and graphs, should only be a few pages. Note the lab handout  , including the data sheet,  will contain all the elements arranged in the following format:. 

(A) COVER SHEET 

Must include: name of experiment and date performed; group partners, individual names and roles; Instructor's name; course and lab section numbers.

(B) INTRODUCTION/ABSTRACT 

#Brief statement (1 paragraph) describing the goals of the lab and methods/procedure used .Do not merely duplicate the laboratory handout  description.   

#Written in a way that a person not familiar with the lab can quickly understand what the goals and methods used are.  

Here is an example of a sentence from an abstract  "Using the electronic picket fence method,  we found the acceleration of gravity to be 9.9 m/s2 + or - 0.9 m/s2. "  Here the goal, or purpose,  is clearly to measure the acceleration of gravity. One could explain briefly the picket fence method.  The absolute uncertainty of 0.9 m/s2 (discussed below)  is quoted.

The statement  may be written in terms of a hypothesis. For example, "The purpose  of this experiment is to test the hypothesis that this resistor obeys Ohm's Law. The results display  a linear relationship between the current and the voltage, Thus,  the hypothesis  is  true." 

(C) DATA : A carbonless copy of all handwritten data must be submitted .Show units and uncertainties. Should be well organized and arranged in tables for clarity. Sample printouts of computer generated graphs or tables are appropriate. Show for example  uncertainties in the data points and the uncertainty in the slope of the best fit line. 

If your lab hand out includes a data sheet and graph paper, include data points  and plots here.

(D) ANALYSIS : Outline major calculations and provide an example calculation for each one. Calculate best values and uncertainties (should be done in lab to make sure that the data is correct and sufficient). Include graphs and tables with proper titles and units in sequence or at the end of the report. State the equations used in calculations and define all variables. 

For example, suppose you measured the acceleration of gravity 6 times recorded in your data table--see step (C); and  suppose your minimum, average and maximum values were 9.12, 9.93, and 10.84 m/s2. You can find the uncertainty of the measurement by taking half the difference between the minimum and maximum values. This uncertainty is this case is 
0.86 m/s2= 0.9 m/s2 and you express you result as 9.9 m/s+ or - 0.9 m/s2. These values would be recorded in your data table .

If your lab hand out includes analysis questions to be answered, include them here.


(E) SUMMARY/ERROR: Following upon the above-mentioned analysis,  a short summary (no more than a few paragraphs) considering what could have caused error in your measurement. Include all sources of error (the more insightful the better). Determine the largest source of error and describe how it could be improved. Explain possible sources of systematic error that would effect the experiment's accuracy. Explain possible sources of random error that would effect the experiment's precision.

(F) CONCLUSION Brief (a few paragraphs). Compare your results to accepted values. Discuss what the data shows, why, and what you've learned. If your lab hand out includes  a data sheet and tables , include your comparison here. For example, here you would compute the percent error between your average value 9.9 m/s2  and the accepted value  9.8 m/s2, where 
percent  error = (9.9 - 9.8)*100%/9.8 = 10 %.  Does the accepted value (i.e. 9.8 m/s2.) fall within your range of values (i.e. between 9.12 ands 10.84 m/s2)? Of so, your experiment agrees with the accepted value; in this case, yes. 

Note: Please attaceh questions coming with the lab handouts on separate sheets of paper. Here is an example of lab protocol  we speak on,  with regard to the Ohm'/s Law lab derived from Vernier's experiments:
 

Visit

http://library.thinkquest.org/10796/ch1/ch1.htm

and review rules on sig. figs with respect to multiplication ,
division, addition and subtraction, which are important for the Lab 2
write up, which will be formal and  discussed more in class and email
before the due day this week.
Note for example if a resistor is listed as 51 ohms with a 5 %
precision, we say that max value =
51 + (0.05)*51 = 51 + 2.55. The 2 digit is underlined since you
ultimately would round to the ones place when you complete the sum
with the 51, which is accurate to the ones place and has two
significant digits. Thus max value =
53.55, where the 3 digit is underlined in view of maximum precision
in ones place.     The maximum, when rounded, would be listed as 54
ohms. When you compute the minimum value,  use the same rules.  This
kind of computation will be used to compute answers to analysis
question 3, EXP 25, Ohm's Law lab, for example.

Note that  in the lab report, you will be turning in the preliminary
set up and analysis  questions on ***separate*** sheets from the
formal lab report which contains the sections described here:
http://www.nvaphysics.com/4CSP10/labs/physics_lab_report_formats.htm  .
Note I refer to Ohm's law as an example in the Intro/Abstract
description. It is your task to carefully include the information in
the other  required lab report sections correctly. That means you may
selectively use  information in the  lab handout's analysis
questions. But PLEASE **turn in  the lab handout's preliminary set up
and analysis  questions on ***separate*** sheets from the formal lab
report**.  THANKS, nva