What effect does increasing the mA setting on an X-ray machine have?

Increasing the mA (milliampere) setting on an X-ray machine enhances the quantity of X-ray photons produced per unit of time. This increase in X-ray production results in a higher dose of radiation reaching the film or imaging receptor in the same amount of time.

When the mA is increased, the same exposure can be achieved with a shorter exposure time. This is particularly beneficial in clinical scenarios to minimize the time the patient is exposed to radiation while maintaining the image quality, as less motion blur can occur with shorter exposure times.

The fundamental relationship between mA and exposure time is described by the principle that for a given exposure, increasing the mA allows for a corresponding decrease in exposure time while still achieving an adequate amount of X-ray photons for proper imaging. This is why increasing the mA results in decreased exposure time.