PhysicsChapter 7: Quantum Physics
Compton Effect
The Compton effect
Definition
The Compton effect is the increase in wavelength of electromagnetic radiation when photons scatter from electrons.
Maximum Shift
Compton scattering demonstrates that photons carry momentum. Photon energy: E=hf=hc/λ Photon momentum: p=Ec Therefore: p=hλ When a photon collides with an electron: photon changes direction; electron recoils; scattered photon has lower energy; scattered photon has longer wavelength. Compton wavelength shift: Δλ = λ'−λ and: Δλ = (hmec)(1−cosθ) where: `m_e` = electron mass `θ` = photon scattering angle Maximum occurs for: **θ=180° giving: Δλmax=2h/(mec)**
Formula / Key Relation
**p=hλ Δλ=(hmec)(1−cosθ)**
Exam preparation
Exam Focus
Quick revision
Revision Zone
Review the key facts, formulas and checks before you move on.Compton Effect
Sticky Notes · Quick Revision
Compton:
- photon + electron
- photon scatters
- electron recoils
- `λ' > λ`
60-second revision
- Compton effect demonstrates particle-like momentum of light.
Did you understand this topic?
Your answer is saved with your learning record. It does not mark the topic as mastered.