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Tracking Brownian motion through video microscopy Documents

Main Document

Tracking Brownian motion through video microscopy 

written by Asma Khalid and Muhammad Sabieh Anwar
published by the LUMS School of Science and Engineering

Brownian motion is the random motion of colloidal particles suspended in water, air or any other solvent. In 1905, Einstein argued that this motion is a direct evidence for the atomic nature of matter. Einstein's and Perrin's efforts helped raise the status of atoms from useful hypothetical objects to objects whose existence could no longer be denied.

In this experiment, we will,

1. observe Brownian motion of microparticles,
2. calibrate a compound microscope,
3. use the microscope's built-in camera to record Brownian motion,
4. learn how to extract images and frames from a movie using MATLAB,
5. use some basic and simple commands for image processing,
6. locate and track microparticulate motion,
7. plot Brownian motion in 2-D,
8. observe how the mean square displacement of particles helps calculate Boltzmann's and Avogadro's constants.

Last Modified February 17, 2012