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Pre-Lab Week 2�(due two hours before Lab 1C)

UCLA Physics Department

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Error propagation/Covariance matrix

Error propagation is an important concept. Go over these videos/notebooks to understand how to apply the principles and use code to extract meaningful values.

Notebooks for each of these can be found in the practice folder:

Physics_4AL_2023-24/Practice Notebooks

This video gives an overview of the error propagation principles you will use throughout the quarter.

This video will go over the covariance matrix of the np.polyfit() function and teach you how to extract the uncertainty/error in the slope and intercept.

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Reading data and 2D arrays (review)

  • Watch this video on 2D arrays and this video on reading in csv data files into Python.

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Plotting and fitting (review)

This video reviews plotting in Python.

This video will go over np.polyfit which will help with polynomial fitting of datasets. In 4AL we will use both linear and quadratic fitting (and explore non-polynomial fitting later).

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Downloads and references

  • Arduino IDE download (Version 1.8.x)
  • Arduino Reference
    • https://www.arduino.cc/reference/en/
    • Contains all the references for functions and variables

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Pre-Lab Assignment Submission

  • You should now have enough understanding of error propagation and the covariance matrix to complete the pre-lab assignment for week 2.
  • In addition, perform some simple calculations on the measurement of the speed of sound.
  • Submit the following Jupyter Notebook to Gradescope:
    • Physics_4AL_2023-24/Assignments/Pre-Labs/Pre-Lab-Week-2.ipynb