A quality radiograph is obtained using 5 mAs at 60 kVp and a 200-speed film-screen system.What new mAs is used to maintain radiographic density when changing to a 400-speed film-screen system?

Question

Quizplus · Accepted Answer

$ \frac{5 \mathrm{mAs}}{\mathrm{xmAs}}=\frac{400 \text { speed }}{200 \text { speed }} \rightarrow 400 \mathrm{x}=1000 \rightarrow \mathrm{x}=2.5 \mathrm{mAs} $

A Quality Radiograph Is Obtained Using 5 MAs at 60