Guide 1-1a.  Laboratory Recording and Reporting

Recording

When recording data or writing reports:

  1. Write only in blue or black ink unless instructed otherwise.

  2. If something is incorrect or needs to be measured again, cross it out with an X and include an explanation. Erasing, whiting-out or other obliteration of data are not acceptable scientific practices.

  3. Don't report fictitious data. Don’t report another person's data as your own. If you use another person’s data or if you use data collected in collaboration with another person, give that person credit.

If you work with a partner or partners, each person of the group independently keeps a record of all information about the experiment unless instructed otherwise.

Identify all numbers with a conventional or defined symbol and/or a defining phrase. For example, the first of the phrases below is the best one to identify the frequency of a stroboscope.

Complete phrase frequency, f, of the stroboscope = 50.0 Hz
Incomplete (symbol not provided, name doesn't specify object) frequency = 50.0 Hz
Incomplete (description not provided) f = 50.0 Hz
Incomplete (units of measurement not provided) frequency, f, of the stroboscope = 50.0

Include the appropriate SI units with any number.

Record measurements to the precision of the measuring device. If, for example, you're measuring to the nearest millimeter, write 0.510 m instead of 0.51 m.

Express measurements and results of calculations to the proper number of significant figures.

Reporting

Lab reports generally include the following sections. In some cases, the teacher may direct you to omit some of the sections. Otherwise, be sure to include them.

  1. Heading:  Name of author, name(s) of lab partner(s), course, and date of submission are in the upper-left hand corner. If you don't have a partner, simply write NO PARTNER.

  2. Title:  The full title of the lab is given. Use the same title as given in the lab instructions.

  3. Goal:  The goal is stated. This is usually the same as given in the lab instructions.

  4. Theory:  This section generally presents the physics behind the experiment. If you use shorthand symbols that don't have commonly-accepted meanings, then provide a legend in which you define the symbols that you use. A labeled diagram is often necessary to accompany the theory. State any assumptions implicit in your derivation.

  5. List of Apparatus:  A list of the items of equipment used in the lab

  6. Method:  Describe the procedure you will use to perform the experiment. Include sufficient detail so that someone reading your report could repeat the experiment without having to ask you for additional information. Convince the reader that you have taken necessary care with experimental design and procedure. Include a labeled diagram or diagrams that help describe the set up. Sometimes you will write the method in advance of the lab. In that case, leave sufficient additional space to include notes taken during the experiment to describe any deviations from the method as originally written.

  7. Data: Include all data that you take. Use tables to organize your data when appropriate.  Provide descriptive column headings and include the units.  Note also that units don't accompany the numerical entries. Columns are generally ordered from left to right in a logical order. Data that doesn't naturally fit into a tabular form need to be written above or below the table and clearly identified with a phrase. If you introduce symbols not already defined in the theory section, identify these with a conventional or defined symbol and/or a defining phrase.

  8. Sample Calculations: Provide an example calculation for each formula that you use in the experiment. Always start by stating the formula in words or symbols. Then substitute and reduce.

  9. Graphical Analysis: Most labs require a graphical analysis. Graphs created with software may be printed and taped into your notebook. Guidelines for drawing and analyzing graphs are given here.

  10. Matching Table:  This is required if you do a curve fit. Examples are shown here.

  11. Equation of Fit:  This is also required if you do a curve fit. The equation of fit uses the actual names of the variables and the numerical values of the fit coefficients (with units and rounded to appropriate significant figures).

  12. Error Analysis (quantitative): This part of the error analysis requires estimates and calculations of absolute and relative uncertainties of the individual measurements and quantities calculated using combinations of the measurements. An experimental error calculation is done if an accepted value is known.

  13. Error Analysis (qualitative): This part of the error analysis discusses possible sources of error without reference to the size of the errors. Sometimes you know an error is likely to be present, but you don't have a way to quantify it  Concentrate on discussing potentially major sources of error that relate to the methods of measurement.  If you can say how a particular error might affect the results, then do so.  One phrase that must never appear in this discussion is human error. This is a meaningless term that tells the teacher that you couldn't think of anything substantive to say. Something else that you must never include as sources of error are mistakes. An example of a mistake would be a mistake in calculation. Think of mistakes as things that you can easily avoid by measuring carefully and double-checking your calculations. Errors are inherent in your methods and are generally unavoidable.

  14. Interpretation: With some labs, there will be interpretation questions to answer.

  15. Conclusion: Summarize your methods of measurement and analysis. Specifically state what you found, making it clear whether you met the goal of the experiment. Include numerical results and results of error calculations. Describe ways that you could improve your experimental method.

Writing Formal Lab Reports

Sometimes you may be required to write a formal lab report in a Word document. This report will include the same parts as described above. For a formal report, pay additional attention to the following things.

  • neatness and organization
  • accepted English usage, punctuation, and spelling
  • clarity of expression
  • efficiency of expression (Be complete without being wordy.)
  • paragraph formatting
  • consistent use of fonts

Submitting Your Reports

Notebook reports: Many of your reports will be handwritten, although they may include computer printouts. You'll scan these reports and upload them to BrainHoney.

Formal reports: Sometimes you'll write a formal version of a report in a Word document.These will be uploaded directly to BrainHoney.

Electronic analysis files: Some labs require graphical analysis using Logger Pro. These will usually be uploaded to WebAssign.



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