Models of Light: Light as a Wave
Light can be described as waves that transfer energy. Light waves—also known as electromagnetic waves—are interacting electric and magnetic fields produced by vibrating electric charges. The rate of vibration determines characteristics of the wave, such as wavelength and frequency. Electromagnetic waves can be categorized according to these characteristics. For example, red light has a longer wavelength and lower frequency than blue light.
Watch this video, which helps illustrate that light is a wave.
| Keyboard Shortcut | Action |
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Video: Light | Crash Course Astronomy (Excerpt)
The behavior of light often follows a wave model. This means that, like other types of waves, light acts in predictable ways.
Now, launch the following interactives, which illustrate two important properties of light waves—and all waves.
Take Notes
- Explain how light’s wavelength determines the amount of energy it carries and its color.
- Research or develop a hands-on activity to model different wave behaviors that you could do with your students in class. Jot down your ideas here.
