Physics 312 Lecture: "Reflection and Refraction of Electromagnetic Waves."
Apr 16, 1998
Light waves are one variety of electromagnetic waves
E-M waves are transverse
E-M waves cover a vast span of wavelength and energy
Physicists measure angles of light rays relative to the normal
to a surface
When light waves reflect from a smooth surface, the
angle of reflection equals the angle of incidence
When light moves from one medium to another, it
changes wavelength
changes speed
changes direction
The ratio of the speed of light in a vacuum to its speed in some medium
is the index of refraction of that substance
The wavelength of light in a medium is equal to its wavelength in a
vacuum, divided by the index of refraction of the medium
If a light ray hits a boundary between two media at some angle
theta1 to the normal, it is refracted into the second medium
at an angle theta2 given by Snell's Law:
n1 * sin(theta1) = n2 * sin(theta2)
This lecture discusses material in Chapter 34 and 35 of Serway.
