SCATTERING  :  DEMONSTRATE PREFERENTIAL BLUE-LIGHT SCATTERING BY SMALL PARTICLES.

In this demonstration we shine a circular light beam through two channels.  One contains clear water, the other water laced with skim milk (SKIM vs. other types of  MILK WORKS BEST). 

The (empty here) container and the 6x7 slide projector.

1. Set up for projection through the long axis of the tank to the screen.
2. Use a circular opening slide to get a beam width less than the width of each channel in the tank.
3. Fill up the two sides with water to a depth such that the beam is enclosed.  Clear off bubbles with brush or finger.
4. Compare how the beam goes through the two sides as drops of milk are added and stirred into one side.
5. Keep going until the red beam gets really dim (and most red).
6. Toss out the liquids when done.

Sample images on the screen.