science 10

Electromagnetic (EM) waves are vibrations between an electric and magnetic field that can travel through a vacuum. Unlike mechanical waves, they require no medium.

Key Characteristics:

• Transverse Waves: Fields oscillate perpendicular to wave direction.

• Speed of Light: All EM waves travel at $c = 3 \times 10^8 \text{ m/s}$ in a vacuum.

• No Medium Required: Propagate through space.

• Wave Properties: Have wavelength ($\lambda$) and frequency ($f$), related by $c = \lambda f$.

Electromagnetic Spectrum:

The full range of EM radiation ordered by wavelength/frequency, from longest to shortest wavelength:

1. Radio Waves: Broadcasting, communication.

2. Microwaves: Ovens, radar.

3. Infrared (IR): Heat, remote controls.

4. Visible Light: Visible to humans (red to violet).

5. Ultraviolet (UV): Sunburns, sterilization.

6. X-rays: Medical imaging, security.

7. Gamma Rays ($\gamma$): High energy, from nuclear processes.