Definitions [1]
Definition: Invisible Spectrum
The part of spectrum beyond the red extreme and the violet extreme is called the invisible spectrum.
Key Points
Key Points: Electromagnetic Spectrum
- The visible spectrum lies between violet and red and is only a small part of the electromagnetic spectrum, while regions beyond are called the invisible spectrum.
- The electromagnetic spectrum, in increasing order of wavelength, is: gamma rays, X‑rays, ultraviolet rays, visible light, infrared radiation, microwaves, and radio waves.
- All electromagnetic waves travel with the same speed (3 × 10⁸ m s⁻¹) in vacuum, and they are transverse waves that show reflection and refraction without a change in frequency.
