## Abstract

As was noted in Chap. 1, light exhibits a dual nature: At times, light behaves as a particle, and at other times, as a wave. In this chapter, we will examine the properties of waves and introduce the wave nature of light.

## Notes

## Glossary of Terms

*amplitude*

Maximum displacement from equilibrium in a wave.

*antinode*

Point of maximum amplitude due to constructive interference.

*dispersion*

Variation in the speed of a wave with frequency (or wavelength). The spreading of light into a spectrum of different colors.

*Doppler effect*

Change in the frequency of waves due to motion of the source, the observer, or both.

*frequency*

Number of waves per second.

*hertz*

Unit of frequency; equals one wave per second.

*interference*

Superposition of two or more waves. Constructive interference occurs when the waves are in phase and therefore combine to form a larger wave; destructive interference occurs when the waves are out of phase and partially (or fully) cancel each other.

*linear superposition*

The resultant displacement of two waves at a point is the sum of the displacements that the two waves would separately produce at that point.

*node*

Point of minimum amplitude due to destructive interference of two waves.

*standing*

*wave*

An interference pattern formed by two waves of the same frequency moving in opposite directions; the pattern has alternative minima (nodes) and maxima (antinodes).

*wave equation*

The relationship between wave speed, frequency, and wavelength: *v *=* f*λ.

*wave model of light*

Light consists of electromagnetic waves.

*wavelength*

Distancebetween adjacent crests or adjacent troughs.

## Further Reading

- Hewitt, P. G. (2014)
*Conceptual Physics*, 12th ed. Boston: Pearson.Google Scholar - Kirkpatrick, L. D., & Wheeler, G. F. (1995).
*Physics: A World View*, 2nd ed. Philadelphia: Saunders College Publishing.Google Scholar - Raichlen, F. (2012).
*Waves*. Cambridge, MA: The MIT Press.Google Scholar - Rossing, T. D., Moore, F. R., & Wheeler, P. A. (2001).
*The Science of Sound*, 3rd ed. Reading, MA: Addison-Wesley.Google Scholar