Electromagnetic waves

What are electromagnetic (EM) waves?

EM waves are transverse waves consisting of oscillating electric and magnetic fields that are perpendicular to each other and to the direction of wave propagation.

Speed of EM waves in a vacuum (c)

All electromagnetic waves travel at the same constant speed in a vacuum, which is approximately 3 \times 10^8 meters per second.

Relationship between frequency (f), wavelength (\lambda), and speed (c)

The relationship is defined by the equation c = f \lambda, where the speed of light is the product of its frequency and wavelength.

The Electromagnetic Spectrum

The full range of EM radiation ordered by frequency or wavelength, including radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.

Energy of a photon (E)

The energy of a single photon is directly proportional to its frequency, expressed by the formula E = hf, where h is Planck's constant.

Visible Light Range

The portion of the EM spectrum visible to humans, typically ranging from wavelengths of approximately 400 nm (violet) to 700 nm (red).

Polarization

The property of EM waves that describes the orientation of the oscillations of the electric field vector in the plane perpendicular to the direction of propagation.

Refraction

The change in direction of an EM wave as it passes from one medium to another with a different optical density, caused by a change in its speed.

Source of EM waves

Electromagnetic waves are produced by the acceleration of charged particles, which creates changing electric and magnetic fields.

Ionizing Radiation

High-energy EM waves, such as ultraviolet, X-rays, and gamma rays, that have enough energy to remove electrons from atoms or molecules.