According to the Inverse Square Law, what happens to the intensity of a light source if the distance to the patient is halved?

The correct answer is that the intensity of the light source quadruples if the distance to the patient is halved. This principle is based on the Inverse Square Law, which states that the intensity of light (or any form of radiation) is inversely proportional to the square of the distance from the source.

When the distance is halved, the calculation for intensity reflects this relationship. Specifically, if the original distance is represented as (d), and the new distance is (d/2), the intensity can be expressed as:

[ I = \frac{k}{d^2} ]

Where (I) is the intensity and (k) is a constant. If you decrease the distance to half (i.e., (d/2)), the equation changes to:

[ I' = \frac{k}{(d/2)^2} = \frac{k}{(d^2/4)} = 4 \cdot \frac{k}{d^2} ]

This illustrates that the intensity increases by a factor of four, confirming that when distance is halved, the intensity indeed quadruples. This relationship is crucial in various fields, including chiropractic practice, where understanding light and its effects on the