Chapter 23.6 +23.7 Flashcards
Wave Fronts
The locus of all adjacent points at which the phase of vibration of the wave is the same
(Same speed in the firection of propagation of the wave)
Pressure Crests
The surface over which the pressure is maximum
Planar wave fronts
When the wave fronts are planar, the rays are perpendicular to the wave fronts and parallel to each other
Rays
An imaginary line along the direction of the travel of the wave. Are the radii of the spherical wave fronts.
Interface
A surface separating two transparent materials, such as air and glass, or water and glass
Incident Rays
The rays coming from the light source
Refracted rays
The rays emitted through the interface
Reflected Rays
Rays of light reflected off the refracted rays
Specular Reflection
When reflected rays travel at a definite angle (can be done so by rays bouncing off a smooth surface).
Diffuse Reflection
Scattered reflection from a rough surface (rigid surface)
Index of Refraction
“n”, the ratio of the speed of light in vacuum to the speed of light in the material, c/v
Law of Reflection
Angle of reflection = Angle of incidence, + incident, reflected and normal ray all lie in the same plane
Snell’s Law
Direction change of the ray due to light ray crossing the interface of 2 substances with different index of refractions - need math
Brightness of ray
Depends on the angle of incidence , the 2 index of refractions, and alignment of the electric field of the incident electromagnetic wave with the interface
Normal Incidence (0 degrees)
When the electric field of the incident light is randomly oriented, the fraction reflected is the smallest.
