Extended Project Lab ReportGuidelines

Physics 101/102

In this document we’ll describe and provide samples for extended projectlab reports in Physics 101/102. The structure and style are adapted fromthose used in Physics 202 which are ultimately adapted from actual physicsjournals. As a student in the first-year physics class we don’t expect youto turn in journal-ready lab reports, and our labs aren’t even conducive tothat, but instead see this as a first step with that ultimate goal in mind.

We’ll start by describing each section of the lab report using the guide-lines set out for Physics 200 and then follow that up with some samples ofeach section. Hopefully you’ll see how to put a lab report together usingthis as a reference. As usual, we’re happy to help you out in person too, sofeel free to drop in anytime or make an appointment if you’d prefer.

1 Description of Report Sections

The sections listed below are what we use in Physics 202 lab reports. We’veadapted them a bit for use in Physics 101/102, but they’re generally similar.This is just an outline of what a report might look like. At this point inyour career you should feel free to combine, add, or drop sections as you seefit to best cover the experiment you’re doing (for instance the ExperimentalDesign and Procedure sections can be combined).

The reader that you are writing this report for is someone who is also inthe Physics 101/102 class but isn’t doing this particular extended project.They’ve done the homework you’ve done, they’ve done the labs you’ve doneup to this point, and they’re familiar with the same computers, equipment,and software that you are. Keep your reader in mind when writing yourreport. A long time spent delving into why one should care about Newton’slaws is overkill for your reader who, like you, has had two weeks of lectures,conferences, and a lab on it. Similarly your reader is familiar with how touse a computer or Datastudio software so telling them how to double clickto open a program isn’t going to be important information to include inyour report.

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1.1 Overview

• Title, Abstract, and Authors

• Introduction

• Experimental Design

• Procedure

• Results and Analysis

• Conclusion

• Citations

1.2 Title, Abstract, and Authors

Make sure to include a title for your report and to include your name andthe name(s) of your partner(s).

The abstract is the very first part of a full lab report and givesa summary of what was done in the experiment and some of thekey results. A reader should be able to glance through your abstract andget a strong sense of what you did and how successful you were.

The first sentence or two should be a brief description of what you did inthe experiment and how you did it. It will have less detail than the summaryof experiment from your lab ticket but should capture the general gist ofwhat you accomplished. After that you’ll follow with a couple sentencesdescribing key (but not necessarily all) results and, if applicable, youshould compare them with accepted values. Citations or references are notpermitted in an abstract, it must be self-contained.

Overall your abstract should be very short; less than 100 words.Don’t run on and on about what you did, try to keep it to 4 sentences orless. You’ll have to work hard to distill down your two weeks of experimentsand results into just a few sentences. Given that many of our labs consistof a variety of different sections it may be necessary to go a bit longer than4 sentences, but try to keep it as short as possible.

1.3 Introduction

The introduction section is where you lay out the history, context,and framework for your experiment. It generally begins with a littlehistorical background or a discussion of the significance of the experiment.

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It might also include something about the motivation for running the exper-iment (aside from the fact that you’re required to do so for class). It mayalso include previous results from similar experiments that relate to yours.You can cite instances of original work on the topic or recent relevant workthat may apply to your situation.

Following this you may want to include a quick summary of your ex-periment. Depending on how you choose to do things this shortsummary may fit better in the following section, ExperimentalDesign. Feel free to put it where you feel it fits best, but don’t put it inboth sections. There’s no need to repeat this information in multiple places.

What the summary of experiment description does is tell the reader whatto expect and provides a framework for the sections the reader can expectto find in the rest of the report. As you’ve already been doing in your labtickets each week you’ll start off with a summary sentence stating the generalor accepted methodology for your experiment. Then you’ll follow that upwith a brief, qualitative description of the basic parts of the experiment.This can be a few sentences where each one states one of the things you’llbe doing in the lab.

You’re not trying to describe a detailed procedure here, justtell us in broad strokes what you did. You’ll have plenty of time to gointo more detail in the next couple sections of the report.

1.4 Experimental Design

In this section you lay out how what you’re going to do will getyou the answer you’re looking for. In your introduction section youlaid out why the reader would be interested and how, schematically, theexperiment was carried out. Now we want to convince the reader that theexperiment actually does what you claim it does.

It may include a description or a diagram of your setup or ap-paratus to facilitate the discussion. It’s also likely to include some of theessential theory behind your experiment. You will want to introduce keyformulas and equations in this section as well and, although you don’t needto include long derivations, it must be clear where they came from.

Keep in mind that this is not your Procedure section. We don’twant to see the gory experimental details of your experiment here, save themfor the next section.

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1.5 Procedure

In this section you will describe exactly what you did and detailyour setup/apparatus if you didn’t already cover it in the Experi-mental Design section. When we say exactly we don’t mean to includingevery detail. You should write this section as if your reader is someone elsein the Physics 101 class who is doing a different extended project than youare. They have had the same class, lab, and conference experience you have.

You want to give enough information so that a student like you couldrepeat the experiment and attempt to reproduce your results. The key isto give just sufficient information and not more than is needed.For instance, generally model numbers (such as ...a model 3Q4592ITX masskit with 12 masses and 3 holders in a blue box...) and the like aren’t usefulinformation but the type of equipment used is (such as ...a voltage sensorwas used...). You are not rewriting the lab manual, so you don’t need to tellthe user where to plug in equipment or how to use the computer.

Anything that was particularly tricky and might trip up a person try-ing to repeat your experiment might be included here too. Don’t includethings where you made errors or didn’t understand what was sup-posed to happen. We don’t need a stream of consciousness running storyof every tribulation you experienced while doing your lab over two weeks,but if there’s something subtle then you might want to include it.

Given that your procedure is describing what you did in the past you willlikely want to write in the past tense. Procedures should be written inprose, not in list form. If you haven’t included a diagram of your setupor apparatus up to this point you need to include one here.

1.6 Results and Analysis

Here’s where you present the data you collected during your experiment andanalyze it so that the reader sees the significance of what you did. Whatyou present here should support the claims you’ve made up to thispoint in earlier sections.

This section will be a combination of data presented in tables or plotsand a discussion of those results. One without the other isn’t going to workout. You must present data in the form of plots or tables ANDdiscussion of that data, preferably keeping data and discussionnearby. In other words, don’t put 6 plots in the front of this section andhave one page of dense text afterward. Plots and discussion about that datashould be near each other for easy reading. If, in your experiment, you seek

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to replicate another’s results or verify standard values, make sure to includethat comparison here.

When you’re preparing plots and writing discussions keep in mind whatyour goals are. Focus on the things you set out to show and explainand discuss that data, but don’t dwell or present raw data thatisn’t useful or doesn’t directly contribute to the results you’reseeking. Reams of raw position data in table form won’t aid you make apoint that a single plot of velocity versus time might.

Plots and tables should be numbered and captioned. Captionsshould be sufficiently long to convey the meaning of the data in the plot ortable. What that means is it probably needs to be longer than your thinkit should. One sentence is usually good, but sometimes two are requiredto really get all the info needed to understand the plot. Axes on plotsshould be labeled and units should be included every chance youhave.

1.7 Conclusion

You will summarize your results in this section and present anysources of error or improvements in the procedure. The first sentenceis a broad summary of what you set out to do. This is followed up by amore detailed summary of results than that in your abstract (since that onlyhits on key results). One way to think about it is that each sentence canprovide one result and, if possible, a comparison to expected value. Then, ifpossible, write a few sentences on major sources of error or potential waysthe experiment could be improved upon.

2 General Tips

2.1 Diagrams

Diagrams are great. A diagram can save you hundreds of words ofexplanation and helps the reader visualize your setup. It’s stronglyrecommended that your report include a diagram of your setup or apparatussomewhere. Drawing your diagrams by hand is totally fine. Don’t wastehours trying to draw a diagram in unfamiliar software that you could drawby hand in 10 minutes!

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2.2 Equations and Variables

Equations may also be written by hand. Doing equations in Word is painfullyslow so feel free to leave space where equations go in your report and writethem in by hand after you print it. If you’re continuing on in Physics you canget started at some point using LaTex, a typesetting program that makesequations easy to include. You’ll get more chances to learn that in the futureso don’t worry about it now.

Make sure to define all variables that you use in equations.It’s imperative that you make clear what each term in an equation meanssince it’s likely that it’ll be used throughout the report. You only need todefine each variable once though, not at each use. Also, if you talk aboutthe “x-axis” or “y-axis” in your report you must show us what those axescorrespond to. Usually this is best accomplished in a diagram.

2.3 Captions, Labels, and Units

All figures, diagrams, tables, and plots must have a number, cap-tion, and be discussed somewhere in the text of you report. Cap-tions should be descriptive and help the reader understand what’s in thefigure, diagram, table, or plot. One or two sentences is fine, one or twowords is far too short.

All plots should have axes labeled and show units. Units should also beincluded in tables and anywhere else in your report where they might benecessary.

2.4 Citations and Plagiarism

Anytime you use an outside source of information you must cite your source.This includes things you find online, from books, or even other people. Wearen’t concerned with the exact formatting of citations at this point but wewant to see that you’re aware that you’re using outside sources and need tocite. Feel free to either use footnotes or include references in a bibliography.A bibliography is more standard, but either is fine now.

Please re-read the section on Academic Misconduct in the In-troduction of the Lab Manual. It’ll help you understand moreclearly what needs to be cited and what is/isn’t ok in terms ofsharing work or paraphrasing.

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2.5 Data

It’s your job to distill down the data you’ve taken into a digestibleform. Long tables of data aren’t going to make much of a point to thereader, especially when a single plot will convey the same information in ameaningful way. Also, never append large data tables or unnecessaryplots to the end of the report. If you include data in tables or plotsanywhere in your report it must be discussed somewhere as well. Data shownin tables or plots but never discussed shouldn’t ever be in your report. Alldata must include some explanation.

2.6 Editing and Length

It is critical that you edit your report before you turn it in. Scientific papersgo through round after round of editing and peer review before they appearin journals. They don’t come out so clear and concise on the first draft;it’s the product of a huge amount of editing. It’s your job to take yourraw report and go back through it, sentence by sentence, asking yourself,“What am I trying to say here and am I achieving that goal?”

Doing this will help you shorten and sharpen what you’re saying. Whysay it in two sentences when it could be said in one? Many times studentsrepeat themselves in the hope that at least one of the times they’ve saidsomething it’ll be clear. We’d much rather you say it clearly once and cutout any repetitiveness.

Sometimes students stumble when trying to write about complex andtechnical experiments. In those cases the readability of the work usuallysuffers. An easy way to make sure that what you’re saying makessense (and is in complete sentences) is to read it aloud to yourself.You’ll know right away, once you read it aloud, whether what you’re sayingreads well or doesn’t make any sense. You can also read a sentence or twoto a friend and see if they follow what you’re trying to say. If they don’t getit then neither will we.

Editing will also help you keep your report short. For our labs there isno upper limit on pages, but we expect that you should be able to keep yourreport to five or six pages long. Reports longer than that will be heavilyscrutinized and penalized if excessive length is due to poor editing.

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2.7 Experiments with lots of separate sections

3 Samples

3.1 Abstract

Here’s a sample abstract from a recent Physics 200 lab report to help youget a sense of how it’s done.

The charge-to-mass ratio of the electron was measured by analyzing themagnetic deflection of a cathode ray in a vacuum tube. Deflections weremeasured at different strengths of magnetic field and with different voltagesin the electron gun emitting the cathode ray. The charge-to-mass ratio wasmeasured to be (1.5±0.3)×1011C∗kg−1, which is consistent with the acceptedvalue e/me = 1.758820088 × 1011C ∗ kg−1.

Here’s a sample of an abstract for one of your P101 guided labs so youcan see how the rules developed for Physics 200 might apply in Physics101/102.

The motions of two objects in free fall under the influence of gravitywere studied using video analysis techniques. An upwardly thrown ball wasfound to accelerate at −9.4m/s2, a 4% departure from the accepted value of−9.8m/s2. Translations and rotations of the coordinate system were foundto change measured vertical acceleration by sign only. Similar analysis ofa balloon dropped under the same conditions showed constant accelerationuntil a terminal velocity of 1.5m/s was reached.

3.2 Other Samples – Apologies for the formatting

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