The electromagnetic spectrum (log scale)वैद्युत चुंबकीय स्पेक्ट्रम (लघुगणकीय पैमाना)The electromagnetic spectrum (log scale)
NCERT Fig 8.4 · Table 8.1 · Class 12 Physics · Chapter 8 · interactive diagram
Parts and what they mean
- Gamma rays: λ < 10⁻³ nm (10⁻¹² m) (गामा किरणें: λ < 10⁻³ nm (10⁻¹² m)) — From radioactive decay of nuclei and nuclear reactions; used in medicine to destroy cancer cells.
- X-rays: 1 nm to 10⁻³ nm (X-किरणें: 1 nm से 10⁻³ nm) — Made when high-energy electrons hit a metal target (X-ray tube); medical diagnosis and some cancer treatment.
- Ultraviolet: 400 nm to 1 nm (पराबैंगनी: 400 nm से 1 nm) — Sun, very hot bodies, special lamps. Mostly absorbed by the ozone layer; UV lamps kill germs; LASIK eye surgery.
- Visible light: 700 nm to 400 nm (दृश्य प्रकाश: 700 nm से 400 nm) — About 4 × 10¹⁴ Hz (red) to 7 × 10¹⁴ Hz (violet): the only part our eyes detect.
- Infrared: 1 mm to 700 nm (अवरक्त: 1 mm से 700 nm) — Hot bodies and vibrating molecules; heat waves, physical therapy, greenhouse effect, remote controls.
- Microwaves: 0.1 m to 1 mm (सूक्ष्म तरंगें: 0.1 m से 1 mm) — GHz frequencies; klystron, magnetron, Gunn diode. Radar, speed guns, microwave ovens.
- Radio waves: λ > 0.1 m (रेडियो तरंगें: λ > 0.1 m) — Accelerated charges in wires/aerials; about 500 kHz to 1000 MHz: radio, TV, mobile phones.
- Wavelength λ in metres (log scale) with frequency ν = c/λ below each value (तरंगदैर्घ्य λ मीटर में (लघुगणकीय) और हर मान के नीचे आवृत्ति ν = c/λ) — Each tick is 100 times longer than the one above it; the frequency is 100 times smaller.
Original diagram drawn by Simple Learning Hub, based on NCERT Fig 8.4 · Table 8.1. Report a mistake