4. The Electromagnetic Spectrum

Concept Explanation:
The electromagnetic spectrum encompasses all types of electromagnetic radiation, arranged according to their wavelength or frequency. Different regions of the spectrum are used for different applications, from radio waves for communication to gamma rays for medical imaging.

Regions of the Electromagnetic Spectrum:
- Radio Waves: Longest wavelength, used for communication.
- Microwaves: Used in radar and cooking.
- Infrared (IR): Used in night vision and remote controls.
- Visible Light: The range of wavelengths that the human eye can detect.
- Ultraviolet (UV): Used in sterilization and black lights.
- X-Rays: Used in medical imaging.
- Gamma Rays: Shortest wavelength, used in cancer treatment and astrophysics.

Example Problem:
Describe the use of X-rays in medical imaging.

Solution:
X-rays are a form of high-energy electromagnetic radiation with wavelengths shorter than ultraviolet light. In medical imaging, X-rays are passed through the body to create images of bones and internal organs. Since bones absorb more X-rays than soft tissues, they appear as lighter areas on the X-ray film, allowing doctors to diagnose fractures, infections, and other conditions.