We present an inexpensive apparatus for bright field and fluorescence microscopy with video capture, suitable for introductory laboratory courses. Experiments on Brownian motion and the Boltzmann distribution of suspended particles in a gravitational field are described. The Boltzmann constant is measured in three ways, and the results fall within 15% of the accepted value.
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For instructions on how to remove the lens from an iSight camera, see <http://www.fas.harvard.edu/~scphys/isight/camera_mod.htm>.
8.
There are many inexpensive consumer-grade LED light sources such as the Sylvania “Dot-it Swivel” that can be used in place of a custom device with or without the microscope mirror.
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See Ref. 9. Interpolation of temperature data in Table 1.
© 2009 American Association of Physics Teachers.
2009
American Association of Physics Teachers
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