Physics A-Level
first minimum
What first minimum means in Physics A-Level, as defined for AQA.
Definitions of first minimum
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Reference: AQA
Occurs at an angle θ where sin θ ≈ λ/D, with D the nuclear diameter and λ the de Broglie wavelength of the electrons.
The angle θ in the scattered electron intensity pattern that satisfies sinθ ≈ 1.22λ/(2R) and gives the radius R.
Topics that use first minimum
- Nuclear radius (A-level only) (AQA A-Level)
Related terms
- Closest approach
- de Broglie wavelength
- distance of closest approach
- Nuclear density
- Nuclear radius
- Proportional reasoning in nuclear physics
- Relationship between radius, volume and density
- Scale and structure of the nucleus
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