Half-value thickness
What Half-value thickness means in Physics A-Level, as defined for AQA, OCR.
Definitions of Half-value thickness
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Reference: OCR
The half-value thickness x½ satisfies x½ = ln2/μ, the thickness that reduces intensity to half its initial value.
The thickness x½ at which I = I₀/2, related to μ by x½ = ln 2 / μ and independent of the initial intensity.
Topics that use Half-value thickness
- Absorption of X-rays (A-level only) (AQA A-Level)
- Nuclear fission and fusion (OCR A-Level)
Related terms
- Alpha and beta decay
- Attenuation coefficient
- Barium
- Binding energy
- Binding energy per nucleon against nucleon number curve
- Chain reactions
- Characteristic X-rays from shell transitions
- Compton effect
Using Half-value thickness in the exam
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