According to the inverse square law, if the source-to-image distance (SID) increases, how does the receptor exposure change?

The inverse square law is a fundamental principle in radiography that describes how the intensity of radiation changes with distance from the source. According to this law, the intensity of radiation is inversely proportional to the square of the distance from the source.

As the source-to-image distance (SID) increases, the radiation intensity reaching the receptor decreases significantly. Specifically, if you double the distance from the source, the intensity of the radiation is reduced to one-fourth. This results in lower receptor exposure because the amount of radiation reaching the receptor is diminished due to this increased distance.

Therefore, when the SID increases, the receptor exposure will decrease accordingly. Understanding this relationship is crucial for radiographers to ensure optimal imaging while minimizing patient exposure.