Brownian Motion With Tv


To demonstrate Brownian motion.


Brownian motion cell with laser on TV monitor, with matches and lab tissue.


Setup Time

5 min.




    A smoke cell is mounted on a tube connected to a TV camera. On the end of the tube inside the cell is a microscope lens which casts an image of smoke particles in the cell onto the videcon of the TV camera. The focal plane of the microscope/TV system is illuminated by a laser to avoid creation of convection currents by heating with a more powerful light source. A twisted lab tissue is burned and blown out, and while it is smoking the rubber bulb on top of the smoke cell is used to snort smoke into the cell through a tube in the bottom of the cell. After about 30 seconds convection ceases and B


    N. David Mermin, Two Models of Brownian Motion, AJP 29, 510-517 (1961). Brownian Movement Corridor Demonstration, AJP 32 #7, vi (1964). J. A. Earl, Brownian Motion Determination of Avogadro's Number, AJP 33, xxi (1965). Noel A. Clark and Joseph H. Lunacek, A Study of Brownian Motion Using Light Scattering, AJP 37, 853-855 (1969). Noel A. Clark, Joseph H. Lunacek, and George B. Benedak, A Study of Brownian Motion Using Light Scattering, AJP 38, 575- ? (1970). C. D. Anger and J. R. Prescott, A Monte Carlo Simulation of Brownian Motion in the Freshman Laboratory, AJP 38, 716-719(1970). George