Find the intensity at a new distance from a point source, or the distance needed to reach a target intensity. The relationship is I₁d₁² = I₂d₂²: doubling the distance reduces the intensity to one quarter.
When solving for distance, remember to take the square root. The member worked solution shows how to rearrange the formula and substitute your values.
Results, input checks, source references and accuracy notes are free. Paid membership adds the step-by-step solution and calculator keystrokesKey sequences for 14 calculator optionsScientific — commonly exam-legalTI-30XaTI-30X IIS / IIBTI-30XS MultiViewTI-34 MultiViewTI-36X ProCasio fx-991EX ClassWizCasio fx-115ES PlusCasio fx-300ES PlusSharp EL-W516TOn screen, no handheld neededRadCon calculator (on screen)Graphing / programmable — practice at homeTI-84 Plus CE (and TI-83/84 family)Casio fx-9750GIII / fx-9860GIIIHP 35sNot sure which you haveGeneric scientificChoose the calculator you use to practice. Check with your testing site which models are allowed in the exam..
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Use this calculator for study and reference. For operational radiological work, follow your site’s controlled procedures and approved references.
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