Most everyone knows that an equilateral prism will refract white
light into its constituent colors: a spectrum ranging from red
to violet. But, if one uses an additional prism, there’s much
more to be discovered. All that’s required: - a source of white
light - a slit mounted on a large piece of cardboard - two
equilateral prisms - two small pieces of card stock - a square
of ground glass. The light source and slit are arranged as
shown. A fairly narrow (1/4”) color spectrum will be displayed
on the ground glass. Note that the light beams are DIVERGENT.
The color spectrum from one prism is now passed through a second
prism. The various color beams are further spread to result in a
somewhat wider (5/16”) spectrum display on the ground glass. The
light beams are even further DIVERGENT. A SINGLE COLOR
EXPERIMENT Isaac Newton wondered if any single color of a
spectrum could be further broken into more colors. To
investigate this, he placed ‘STOPS’ in the light beams between
the two prisms – allowing only one colo