Distance & Shielding: The Inverse-Square Law and Half-Value Layers
This lesson is part of the course
In this lesson
You calculate how the dose rate of a Cs-137 point source falls with distance and with lead thickness, how much lead brings it to a target, and the dose rate at a work position that uses both.
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Lessons in this course
- The Decay Law N = N0·e^(−λt) and λ from the Half-Life Locked
- Activity A = λN: Becquerel, Curie and Specific Activity Locked
- Remaining Fraction after n Half-Lives, Replacement Time & a Decay Chart Locked
- Radiocarbon Dating: Age from the Remaining Fraction of C-14 Locked
- Decay Chains: Parent → Daughter Ingrowth in a Step Table (Sr-90 → Y-90) Locked
- Distance & Shielding: The Inverse-Square Law and Half-Value Layers Locked
- Dose Estimates: Dose Rate × Time, Weekly Totals and an Annual Comparison Locked
- Medical Isotope Logistics: Ordering Tc-99m and F-18 Despite the Decay Locked