Radiation Safety Practice Exam

According to the inverse square law, how does distance affect radiation exposure?

1. Exposure increases linearly with distance

2. Exposure is unaffected by distance

3. Exposure decreases exponentially with distance

4. Exposure increases exponentially with distance

The correct answer is: Exposure decreases exponentially with distance

The correct response regarding the impact of distance on radiation exposure according to the inverse square law is that exposure decreases exponentially with distance. This principle states that the intensity of radiation is inversely proportional to the square of the distance from the source. When the distance from the radiation source doubles, the radiation exposure is not just reduced by half, but rather by a factor of four because it is related to the square of the distance. For example, if you move from 1 meter away from a radiation source to 2 meters away, the exposure decreases to one-fourth of what it was at 1 meter. This relationship illustrates an exponential decrease in radiation exposure as one moves farther from the source, highlighting the importance of maintaining a safe distance to minimize exposure effectively. Understanding this concept is crucial in radiation safety practices since it informs protocols about safe distances to maintain during exposure to radioactive materials or sources.