Lab Report Guidelines
PHY 141/142/161/162 Lab
Instructor: Dr. Balduz
Each lab report should consist of the following parts: introduction, background, data, analysis, conclusion,
and any additional questions to be answered. Included below is a prescription for what should be included
in each part, along with a typical breakdown of the lab grade in percentage of total points for each part.
1. Introduction (15%): This is the first part of the report. It should be on a single page containing the
names (and signatures) of the students submitting the report, the course name and semester (e.g., PHY
161Lab Fall 2015), the lab title, and a description of the lab purpose or goals. This should be brief and
to the point, usually only one paragraph, stating clearly but concisely why we did this lab. In some cases
we are verifying some equation or theory; in others we are studying the properties of some object or
material; in any case there is always a goal. Please leave ample “white space” on the page, so the
instructor can write the grades on this first page.
2. Background (15%): This should contain both practical and theoretical aspects of the lab. The practical
background is a description of the actual system we used, and how we made our measurements. The
theoretical background explains the basis for our understanding of our systems, including conceptual
aspects of the relevant theories or models, simplifying assumptions and approximations, and relevant
equations.
3. Data (20%): Following the introduction, place any data tables and graphs from the lab.
4. Analysis (30%): After the data, include a discussion of the results. This should be fairly detailed,
including numbers from the tables and graphs. There may be a theoretical prediction, which needs to be
checked against the data; so we might calculate a percent difference %Diff (theory, experiment) and use
that to decide whether or not the lab confirms the equation or theory. There may be numbers that we
measure, that represent physical properties of the materials at hand; so we might calculate a percent
variation %Var (property) and use that to decide whether that property really is fixed by a single number
as expected. There are usually one or more measures of the uncertainty of the lab measurements; so we
calculate %Unc (measurements). All of these need to be quoted and compared, so each part of the
results can be judged. This should be a detailed analysis that does not attempt to give the reader the “big
picture,” but a certain amount of discussion may be appropriate, to explain what the numbers mean and
what the results say about the procedure we used.
5. Conclusions (20%): This should be a brief but comprehensive statement of what the lab achieved,
usually no more than one paragraph. It should relate specifically to the goals stated in the introduction,
and the issues discussed in the background. Can we confirm the equation or theory, based on the
detailed results given above? Does the system or material really have a constant property as expected?
Did the lab equipment and procedure serve the purpose well or not? Here is the place for global
conclusions; the detailed numbers have already been provided in the analysis portion of the report. In
addition, we may suggest improvements on our models or procedure, or consider what follow-up labs
we would like to do next…
6. Questions (variable %): At the end of some lab instructions there is a list of additional questions. Your
instructor may select some of these for you to answer and they should be at the end. Some questions
should be answered with reference to your specific results, while others will be more general or
theoretical…