General notes

A lab report is not an essay where you are graded and paid by its length! The shorter it is the better. I would say you should limit yourselves to about 2 pages, maybe 3 if you have a lot of plots. The most prestigious physics journals usually limit publications to 3 pages. The Nobel prize winning paper “GW151226: Observation of Gravitational Waves from a 22-Solar-Mass Binary Black Hole Coalescence” has it content fit to 7 pages.

We will penalize unnecessary long reports!

The good lab report is self contained. I.e. a reader should grasp why you are doing your lab, how you do, what did you get, how you interpret the data, and what are the conclusions. Ideally, based on the experiment description a reader should be able to recreate the experiment.

Required lab reports sections

Any lab report must have the following sections

• Header
  • Title
  • Author list (Submitter and lab partners when applicable)
  • Submission date
  • Abstract (What was done and what was obtained)
• Introduction
  • How is this lab fits in the overall physics context, i.e. big picture
  • What is its significance in the development of modern physics
  • Where else this measurement technique is used
• Underlying theory
  • Theoretical formulae, including description of every parameter
  • Theoretical graphs when applicable
• Experiment description
  • Sketch of the experiment
  • Short description of the data acquisition procedure
  • What are the settings
  • Connection between measured values and parameters in the theoretical formulae
• Data analysis
  • If you have only a few data points, it is OK to present them in a form of a table, so we can check your analysis.
  • The main way to present scientific data is using PLOTS!!! If you changed something and measured outcomes, make a plot of such dependency. You probably have a table in you logbook, but report must have the plot of this dependency. Any plot must have
    • caption
    • axes labeled and with units
    • data points
    • if you plot more than one trace, use clearly distinguishable markers and the legends explaining each trace (color change is not sufficient: most of the people still print in black and white; a journal will charge you extra for colors)
    • a fit based on the theory
    • DO NOT USE JPEG file format for your plots
  • Error analysis
    • uncertainty estimate (error propagation) and how it was obtained
    • comparison of statistical uncertainty with the one obtained via error propagation method, if applicable
    • how good is the fit, i.e. residuals discussion
• Conclusions
  • Short summary of results
    • Did experiment work, matched the theory or not
    • If you have an expected value (which is for the most of the labs because we are recreating someone else experiments), did it match or not
    • If there is a discrepancy, what is the source of it
• Bibliography (when appropriate)
  • This is the way to avoid repeating calculations already published elsewhere. For example, “see the complete proof of the equation above in [Reference]”.
  • If you have to look up a value of any constant, cite the source
    • Hint. Most of the time it is the lab manual

Approximate weight of the lab report sections

Remember

• if you have a number, it must have a unit.
• uncertainty must have no more than one significant digit (the only exception if the first digit is one).