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Inverse Square Law - Math - Video Lesson

Hey, everybody. Welcome back. In this video, we're talking about inverse square math. So remember that when the distance between the x-ray source and the point of interest changes, several things about this exposure change. The concentration or quantity of x-ray photons in the x-ray beam changes. Also, the concentration of x-ray photons striking the patient changes. That's the patient dose. And lastly, the number of photons striking the receptor also changes. We call that the receptor exposure. All of these relationships follow the inverse square law. So if the distance increases, The beam intensity at the patient decreases, the patient dose decreases, and the receptor exposure decreases. This is called the inverse square law because when one variable goes up, all