Lecture 11. E. 1. Frequency vs. Wavelength

Electromagnetic waves move at the speed of light c, as reflected in this formula:

wavelength is the DISTANCE between two points on the wave the are the same --

frequency is how often complete wavelengths moves past an observer --

a DISTANCE, multiplied by HOW OFTEN you travel it, is a SPEED, in meters/sec, as this analogy with trains might illustrate:

By analogy, crests of long wavelength light pass observers more slowly, and crests of short wavelength light pass more quickly.