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Mathematics 309 - Spring 2003
2. Rays or waves?
Summary: energy, frequency, transverse components.
All traveling in waves. Pretending to be rays.
What is light? In this course, light will be
waves of energy distributed in space.
(We'll not look at photons and quantum mechanics,
as far as I can see.) However, light seems to travel
along rays, perpendicular to the waves.
It comes from somewhere, doesn't it?
How is that? Psychological reasons, physical reasons.
In any event, much
of the time in this course
we'll treat light as if it traveled along rays.
What is colour? Energy has different frequencies.
The colour sensitive parts of the eye act as filters.
What is polarization? The energy has transverse direction.
Refraction. From wave motion.
Wave velocity. Rays bend.