Original file (Ogg Theora video file, length 3.4 s, 1,050 × 425 pixels, 423 kbps)
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Summary
DescriptionCollimated and penetration.ogv
English: This animation shows how directional information, related to the location of a radioactive source, can be inferred with use of a collimator. The radioactive source is dead centre on the plane of the collimator face Dscraggs
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