Modern Physics

  • WM5.1 Cloud Chamber

    This is a homemade cloud chamber. A piece of dry ice sets in a pool of methanol in a styrofoam box. A metal plate lies over the dry ice bath which keeps the plate cold. On top of this box a plexiglass chamber perfectly fits. There are green strips in the chamber that have to be soaked in methanol. A layer of supercooled alcohol is created at teh surface of the plate. A TV camera can be used to that everyone can see. Rub the top of the chamber to create an electric field which clears away condensed droplets--a dry day is preferable. Using a supplied alpha source, the particles leave a cloudy trail, just like a bubble chamber.

  • WM5.2 Expanding Universe

    A balloon covered with dots is attached to this stand and then to an air hose from the table. As the air fills the balloon, the dots are moving away from each other. Imagine these dots being galaxies. As the balloon fills more, the dots are moving away from each other faster and faster.

  • WM5.3 Frank Hertz

    This is a simplified model of the classic experiment.

  • WM5.4 Photoelectric Effect

    This is done in lab. A PASCO photoelectric effect apparatus is used with a mercury lamp to create a current as photons strike a special metal. The manufacturer has already put a clear filter on the bulb, so do not worry about exposure to ultraviolet light.

  • WM5.5 Spectrometer

    This is an old spectrometer. It has two inserts, one for a sample and one for a blank. It measures transmission percentage and optical density.