De Broglie Wavelength
Also known as matter wave · wave-particle duality
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Constant used — built into this formula, no need to enter
Planck constant · exactLearning zone
De Broglie's 1924 thesis proposed that if waves can be particles, particles must be waves — with wavelength h/mv. Three years later, electron diffraction proved it. An electron accelerated through 100 V has λ ≈ 0.12 nm, comparable to atomic spacing, which is why electron microscopes resolve details a thousand times finer than light ever could. For anything macroscopic the wavelength is absurdly small — a walking human is around 10⁻³⁶ m — which is why billiard balls never diffract.
De Broglie Wavelength
Where
- = De Broglie wavelength
- = Mass
- = Speed
Missing one of these? Work it out first, then come back
- De Broglie wavelength — Photon Energy from Wavelength (E = hc/λ), Photon Momentum (p = h/λ)
- Mass — Newton's Second Law, Kinetic Energy
- Speed — Speed, Distance & Time, Kinetic Energy