Introduction to SAT II Physics

One of the more common ways of testing wave optics is by testing your familiarity with
different terms. We have encountered a number of terms—diffraction, polarization,
reflection, refraction, interference, dispersion—all of which deal with different
manipulations of light. You may find a question or two that describe a certain
phenomenon and ask which term explains it.
EXAMPLE

Which of the following phenomena does NOT affect the direction of a wave of light?

(A)Dispersion

(B) Polarization

(C) Diffraction

(D)Reflection

(E) Refraction

The answer to the question is B. Polarization affects how a wave of light is polarized, but
it does not change its direction. Dispersion is a form of refraction, where light is bent as it
passes into a different material. In diffraction, the light waves that pass through a slit
then spread out across a screen. Finally, in reflection, light bounces off an object, thereby
changing its direction by as much as 180º.

Key Formulas

Frequency of

an

Electromagnet

ic Wave

Law of

Reflection

Index of

Refraction

Snell’s Law

Critical Angle

Focal Length

for a Spherical

Concave

Mirror

Mirror and

Lens Equation