How to write a good lab report?


The objective of this paper is to teach you how to write a good lab report and draw your attention to the common mistakes and the bad habits that some or most of the students do from my experience of teaching physics labs. Itís crucially important for you to read this paper thoroughly, understand it, and follow its instructions. You can bring it with you in each lab to refer to it when needed.



The theory behind writing a good report is very simple: Record what you have done in the lab accurately in a clear manner and comment on your results in a smart way. So we can sum up this theory in the following equation:

Accurate Recording + Clear Presentation + Smart Analysis and Good Discussion = An Excellent Report.You will find the theory behind the experiment in the lab manual, and I will try to make it clear before doing the experiment (after your prelab quiz). Still, you should write the theory in your own words. Try as much as possible not to copy from the lab manual but express what you understood in a way more similar to what I did before doing the experiment. DONíT write a list of equations. You should speak a little about the importance of each equation, the parameters involved in it, Öetc. You have to define each symbol used.



Before writing this paper more than one year ago, I surfed the internet for resources on how to write a good lab report. I started writing, taking into consideration the most common mistakes done by students. This paper has been modified twice since then. In the procedure part, write the steps you have followed in the experiment to achieve the goal(s) you mentioned in the objective. Again: DONíT copy from the manual (or from your friend E a fatal error), rather, record the steps you did by your hands. You donít have to read what you were doing a few minutes ago from the manual. Still, you can refer to it.


Data analysis

I have no data to give you in this paper except that the grade of most students is determined by their lab reports since it constitutes the majority of the lab grade. When you analyze the data taken in the experiment, present your measurement results in a clear, tabulated way. Each number should be followed by its unit. A graph should be neat and fill the whole page. Write the label and units on each axis. You will do some calculations on the data, show them in detail, donít write the final answer directly. Take care of the proper number of significant digits. It's unreasonable if you found out the speed of sound from our simple 102 experiment to be 343.475993484 m/s !!


Sources of error

Of course every human work has a possibility of error. This paper for example may have ignored or exaggerated some factors that affect the quality of your report (and of course your grade).There is no perfect experiment. State as many sources of error as you can, but donít mention silly ones. Never use the term "Human Error" without saying what type of human error.


Uncertainty Analysis

Although the instructions in this paper are very important to improve your grades in the lab, there is a very small probability that outstanding students that donít stick literally to these instructions may get a good grade by performing well in the final lab exam and showing a great deal of understanding of what they have done when writing their report. Express your uncertainty of the quality of your results in a quantitative manner. State how your data agree or disagree with theoretical values (the precision). Usually results in this part are expressed in percentage ratios.



I have presented some guidelines that hopefully will help you write a professional report that can be read and understood easily by anyone unfamiliar with the experiment. In this part- the conclusion- state whether you achieved your goal stated in the objective part or not and why, the most important result of the experiment, whether the error is within your expectation or not, what you learned from the experiment, what you suggest to improve it, what can the experiment be applied to,Ö.etc.

This part shows whether you understood the experiment or not.

General advices

ß         You should assume that the reader of your report doesnít know anything about the experiment, and he doesnít know what you have done. The report should be readable.

ß         You HAVE to mention your group number or the names of your partners on each report

ß         Donít forget to answer the questions in the lab manual

ß         Similarities between your report and your partners' will affect your grade.

Tareq Ahmed Mokhiemer