Question

increasing the source - to - image distance (sid) will result in which of the following?
increased quantity and increased quality of photons
decreased quantity and decreased quality of photons
increased quantity and will have no effect on the quality of photons
decreased quantity and will have no effect on the quality of photons

Explanation:

The intensity of the x - ray beam (quantity of photons) follows the inverse - square law. As the source - to - image distance (SID) increases, the intensity of the x - ray beam decreases. The quality of photons is related to factors like kVp and filtration and is not affected by SID.

Answer:

Decreased quantity and will have no effect on the quality of photons