📡 Electromagnetic Spectrum

radio · microwave · infrared · visible light · ultraviolet · x-ray · gamma ray

RADIO
MICRO
IR
VISIBLE
UV
X-RAY
GAMMA
← Longer wavelength / Lower frequency / Less energy Shorter wavelength / Higher frequency / More energy →
Enter wavelength → calculate frequency & energy
Wavelength (λ) nm
Enter frequency → calculate wavelength & energy
Frequency (f) Hz
What is this?

The electromagnetic spectrum is the full range of all electromagnetic radiation — from the lowest-energy radio waves to the highest-energy gamma rays. All EM radiation travels at the speed of light (3 × 10⁸ m/s) in a vacuum; only wavelength and frequency differ.

Why does it matter?

Nearly every modern technology uses some part of the EM spectrum — radio, WiFi, TV, remote controls, MRI scanners, X-rays, and even the light you're reading this by. Understanding the spectrum is fundamental to physics, medicine, astronomy, and communications.

Key terms
Wavelength (λ) — distance between two wave peaks; measured in metres or nanometres (nm) Frequency (f) — number of wave cycles per second; measured in Hertz (Hz) Speed of light (c) — 3 × 10⁸ m/s in vacuum; c = λf links wavelength and frequency Photon energy (E) — E = hf (Planck's equation); higher frequency = more energy per photon Ionising radiation — radiation with enough energy to remove electrons from atoms (UV, X-rays, gamma)
🎯 Try this challenge

In the Wave Calculator, enter 500 nm (green visible light). What is the frequency? Now enter 0.1 nm (X-ray). How does the energy compare? Why do X-rays require lead shielding but radio waves do not?

Continue Learning
Stars & Galaxies