physicsa.com
class code: SPS22 teacher: Mr. Elert
classroom: A314 office: A214
test day: Friday phone: (718) 724–8500 ext. 2141
email: elert@midwoodscience.org

Lab Reports

Contents

Graded labs

  • Fall semester
    1. Toy cars (formal report)
    2. Newton's 2nd law (formal report)
    3. Coefficient of friction (formal report)
  • Spring semester
    1. Ohm's law (formal report)
    2. Speed of sound (formal report)
    3. Shoot for your grade (accuracy grade)

Formal lab reports

Components

  1. Cover page [5%]
    Write the title of the lab in the center of the page. Write your name and class period in the lower right hand corner.
  2. Abstract [5%]
    Write a brief statement of what you were verifying, measuring, determining, etc. in the form of a purpose or goal. One sentence should suffice. Your goal is never to "prove" something, as it is only possible to disprove scientific theories. The purpose of every lab is always given in writing on the raw data sheet, in the lab notes, on the whiteboard, or verbally by the lab instructor. Feel free to "copy" this word for word.
  3. Introduction [10%]
    Provide some background to the experiment: concepts, terms, formulas, etc. Present them in logical order.
  4. Diagram [5%]
    Make a rough, labeled sketch of the assembled apparatus. Include labeled schematic diagrams when needed (vector or circuit diagrams, for example).
  5. Procedure [10%]
    Write a brief description of the activities performed during the lab. Gathering or putting away equipment, entering numbers in a table, calculating results, and writing a report are not lab procedures. Use simple past tense, passive voice. Don't tell the reader what to do, describe what was done. Organize the procedures using numbered bullets instead of paragraphs.
  6. Analysis [40%]
    Explain what the data means in words and show how to extract this meaning using mathematics. Items used in analysis can include (but are not limited) to the following:
    • a single data table showing the original data collected and the results calculated
    • the equations used in your calculations
    • a graph with a best fit curve and coefficients
    • descriptive text to tie the whole thing together
    Graphs and tables should be made using Vernier Graphical Analysis 3. The Physical Science Department purchased a site license that allows us to distribute copies to Midwood students free of charge. The installers for Mac and Windows computers are password protected. Your teacher will tell you the password.
  7. Conclusion [10%]
    Summarize what you accomplished through your analysis. Respond to the purpose of the lab as stated in the abstract. One sentence is usually enough.
  8. Sources of error [10%]
    Identify at least two factors that lead to experimental error. Consider the assumptions made in the theory and the materials and methods used to do the experiment. Be specific. Avoid generalities. Mistakes (intentional or adccidental) are not sources of experimental error. Do not use the words wrong, right, precise, imprecise, accurate, inaccurate, perfect, imperfect, etc.
  9. Raw data [5%]
    This is to be the actual paper containing the measurements gathered during the lab itself. Do not rewrite it. Do not use whiteout. Neatness is not crucial. Honesty is.

Formatting

Grading

Elements of a good computer drawn graph

Annotated screenshot

How to write an experimental procedure

The procedures section of a lab report for this class should be written using declarative sentences in simple past tense with a passive voice. Avoid the active voice and never write imperative sentences.

Declarative vs. imperative sentences

Like recipes, lab instruction sheets use imperative sentences with an implied future tense. They describe what will be done in the lab. Imperatives are command sentences that have no subject. When you come across a sentence that says "Do this" or "Do that" in an instruction sheet, it is implied that "You will do this" or "You will do that". You, the student in lab, are the subject of these imperative sentences. The reason lab instructions are written this way is because you will be doing what is written in that document.

In contrast, student lab reports use declarative sentences written in simple past tense for the procedures section. They describe what was done in the lab. The reason lab reports are written this way is because you did what is written in that document.

Passive vs. active voice

Passive voice is preferred in scientific writing since the agent performing the action is obvious and unchanging. In the case of lab reports for this class, the agent is a group of students that includes the author of the lab report.

Passive voice gives priority to the object being acted upon. Sentences in passive voice begin with the most important information first — what piece of equipment was used or what measurement was made. These are what matters in a procedure, so sentences should start with them. As they say in journalism, "Don't bury the lead".

Two procedures from different lab reports about the same experiment

imperative & active

 

declarative & passive

  1. Prepare the materials needed: a meter stick, a stopwatch, 5 different masses, a Triple-beam Balance, and a protractor.
   
  1. Weigh all 5 masses one at a time with the electronic balance.
 
  1. Five different hooked masses were selected and weighed on an electronic balance.
  1. Set up a pendulum by hanging one of the 5 masses on one end of the string. Suspend the mass and the string to the metal bar with a certain length.
 
  1. A pendulum was constructed by suspending one of the masses from a string attached to a horizontal clamp.
  1. Using a meter stick, measure the length of the string of the pendulum.
 
  1. The length of the pendulum was measured with a meter stick from the center of the mass to the bottom of the clamp.
  1. Using a protractor, bring the string back to a certain angle.
 
  1. A protractor was placed near the top end of the string so that its cross hairs were aligned with the point of suspension. The mass was pulled back until the angle between the string and the vertical was some convenient value.
  1. Release the pendulum and record the time it takes for 10 complete oscillations. Then calculate the period using the formula.
 
  1. The pendulum was released and the time for 10 complete oscillations was measured with a stopwatch.
  1. Test for the effect of length. Angle is kept constant at 60°. Mass is kept constant at 0.089 kg. Repeat step 6 with the other 4 different lengths.
 
  1. To test the effect of length on period, the experiment was repeated with varying lengths for a total of 5 trials. The mass on the end of the string and the angle of release remained constant during this portion of the experiment.
 

The student in the first column listed the equipment in step 1. Don't do this. Experimental procedures are not written like recipes.

The student in the first column also described a calculation in step 6. Don't do this. Calculations belong in the analysis section of a lab report.

Top ten stylistic errors I never want to see in a lab report

Words, phrases, and sentences of this sort must never appear in a lab report.

  1. Wishy-washy phrases
    • "maybe"
    • "might have"
    • "may have"
    • "could have"
    • "should have"
    • "possibly"
    • "sort of"
  2. Nonspecific excuses
    • "old equipment"
    • "outdated equipment"
    • "bad equipment"
    • "dirty equipment"
    • "not enough time"
    • "inadequate time"
    • "human error"
  3. Space filling sentences
    • "Before beginning this lab we must define terms".
    • "In conclusion…"
    • "There were many sources of error in this lab".
  4. Any sentence using the words "data", "information", "relationship", "represent"
    • "We wrote down the data".
    • "This is a graph of our data".
    • "Then we analyzed our data".
    • "The graphs below show the information from the table".
    • "The table and graph represent the relationship between…"
    • "Every tick of the metronome represented…"
    • "Each data point represents…"
    • "The slope represents the relationship…"
    • "I interpreted my data to show the relationship…"
  5. Pretty much any phrase containing the words "wrong" or "right" (except when referring to a "right angle")
    • "We measured wrong".
    • "We did not use the ruler the right way".
    • "We wrote down the wrong numbers".
    • "We did not calculate the right answers".
    • "The measurements caused us to calculate the wrong answer".
  6. Spelling errors that won't be caught by a spell checker
    • "fro" when you mean "for"
    • "angel" when you mean "angle"
    • "trails" when you mean "trials"
    • "censor" when you mean "sensor"
    • "photo gate" when you mean "photogate"
    • "than" when you mean "then" (or vice versa)
    • "weight" when you mean "weigh" (or vice versa)
    • "of" when you mean "have" (or vice versa)
    • "there", "their", and "they're" have different meanings
  7. Words that confuse science with mathematics
    • "prove"
    • "proves"
    • "proven"
    • "proved"
    • "proof "
    • "proofed"
  8. Words that assume science is the pursuit of perfection
    • "exactly", "inexactly", "exact", "inexact"
    • "perfectly", "imperfectly", "perfect", "imperfect"
    • "precisely", "imprecisely", "precise", "imprecise"
    • "possibly", "impossible", "possible", "impossible"
    • "accurately", "inaccurately", "accurate", "inaccurate", "a Accura"
  9. Comparative statements that don't make a comparison
    • "The force of friction was greater". (Greater than what?)
    • "The mass was more". (More than what?)
    • "The speed was very fast". (Fast compared to what? How fast is very fast?)
  10. Textspeak
    • "u"
    • "r"
    • "gr8"
    • "i"
    • "¯\ˍ(°͜°)ˍ/¯"

Formal lab reports in the Common Core standards

Writing Standards for Literacy in History/Social Studies, Science, and Technical Subjects: Grades 11–12 students.

  1. Write arguments focused on discipline-specific content.
    1. Introduce precise, knowledgeable claim(s), establish the significance of the claim(s), distinguish the claim(s) from alternate or opposing claims, and create an organization that logically sequences the claim(s), counterclaims, reasons, and evidence.
    2. Develop claim(s) and counterclaims fairly and thoroughly, supplying the most relevant data and evidence for each while pointing out the strengths and limitations of both claim(s) and counterclaims in a discipline-appropriate form that anticipates the audience's knowledge level, concerns, values, and possible biases.
    3. Use words, phrases, and clauses as well as varied syntax to link the major sections of the text, create cohesion, and clarify the relationships between claim(s) and reasons, between reasons and evidence, and between claim(s) and counterclaims.
    4. Establish and maintain a formal style and objective tone while attending to the norms and conventions of the discipline in which they are writing.
    5. Provide a concluding statement or section that follows from or supports the argument presented
  2. Write informative/explanatory texts, including the narration of historical events, scientific procedures/experiments, or technical processes.
    1. Introduce a topic and organize complex ideas, concepts, and information so that each new element builds on that which precedes it to create a unified whole; include formatting (e.g., headings), graphics (e.g., figures, tables), and multimedia when useful to aiding comprehension.
    2. Develop the topic thoroughly by selecting the most significant and relevant facts, extended definitions, concrete details, quotations, or other information and examples appropriate to the audience's knowledge of the topic.
    3. Use varied transitions and sentence structures to link the major sections of the text, create cohesion, and clarify the relationships among complex ideas and concepts.
    4. Use precise language, domain-specific vocabulary and techniques such as metaphor, simile, and analogy to manage the complexity of the topic; convey a knowledgeable stance in a style that responds to the discipline and context as well as to the expertise of likely readers.
    5. Provide a concluding statement or section that follows from and supports the information or explanation provided (e.g., articulating implications or the significance of the topic).
  3. Students' narrative skills continue to grow in these grades. The Standards require that students be able to incorporate narrative elements effectively into arguments and informative/explanatory texts. In history/social studies, students must be able to incorporate narrative accounts into their analyses of individuals or events of historical import. In science and technical subjects, students must be able to write precise enough descriptions of the step-by-step procedures they use in their investigations or technical work that others can replicate them and (possibly) reach the same results.
  4. Produce clear and coherent writing in which the development, organization, and style are appropriate to task, purpose, and audience.
  5. Develop and strengthen writing as needed by planning, revising, editing, rewriting, or trying a new approach, focusing on addressing what is most significant for a specific purpose and audience.
  6. Use technology, including the Internet, to produce, publish, and update individual or shared writing products in response to ongoing feedback, including new arguments or information.
  7. Conduct short as well as more sustained research projects to answer a question (including a self generated question) or solve a problem; narrow or broaden the inquiry when appropriate; synthesize multiple sources on the subject, demonstrating understanding of the subject under investigation.
  8. Gather relevant information from multiple authoritative print and digital sources, using advanced searches effectively; assess the strengths and limitations of each source in terms of the specific task, purpose, and audience; integrate information into the text selectively to maintain the flow of ideas, avoiding plagiarism and over reliance on any one source and following a standard format for citation.
  9. Draw evidence from informational texts to support analysis, reflection, and research.
  10. Write routinely over extended time frames (time for reflection and revision) and shorter time frames (a single sitting or a day or two) for a range of discipline-specific tasks, purposes, and audiences.

Source: Common Core State Standards Initiative. (2010). Common Core State Standards for English Language Arts & Literacy in History/Social Studies, Science, and Technical Subjects [pdf].

NYS Board of Regents and College Board requirements

Regents requirements do not apply to students in AP Physics C unless they have not taken the Regents Physics Exam.