Electromagnetic radiation

Definition

Electromagnetic radiation is energy that travels through space in the form of waves. It includes a wide range of wavelengths, from gamma rays to radio waves.

5 Must Know Facts For Your Next Test

1. Electromagnetic radiation can be described by its wavelength, frequency, and energy.
2. The speed of light (approximately 300,000 km/s) is constant for all forms of electromagnetic radiation in a vacuum.
3. Visible light is only a small part of the entire electromagnetic spectrum.
4. Different types of electromagnetic radiation are used for various astronomical observations, such as X-rays for high-energy processes and radio waves for studying cosmic microwave background radiation.
5. The behavior and interaction of electromagnetic radiation with matter are fundamental to understanding astronomical phenomena.

Review Questions

• What determines the different types of electromagnetic radiation?
• Why is the speed of light important in the study of electromagnetic radiation?
• How does visible light compare to other forms of electromagnetic radiation?

Related terms

Wavelength:

The distance between successive crests of a wave.

Frequency:

The number of waves that pass a given point per second.

Photon:

A particle representing a quantum of light or other electromagnetic radiation.