A radiation detector which is located 2.0 meters from a radiation source indicates a radiation intensity of 100. mCi (millicuries). What would the radiation intensity be if the detector was 4.0 meters from the source?

Question

Quizplus · Accepted Answer

The intensity of radiation follows the inverse square law, meaning it decreases with the square of the distance from the source. Doubling the distance from 2.0 meters to 4.0 meters reduces the intensity by a factor of 4 (2^2), so the intensity becomes 100 mCi / 4 = 25 mCi.

A Radiation Detector Which Is Located 2