What type of radiation can be detected by photographic film and fluorescent substances?

The detection of radiation by photographic film and fluorescent substances is indicative of ultraviolet radiation. Photographic film contains chemicals that undergo a change when exposed to light, including ultraviolet light. Similarly, fluorescent substances absorb energy (including ultraviolet radiation) and subsequently re-emit it as visible light, making them useful for detecting unseen radiation.

In contrast, while X-rays and gamma rays also have the ability to expose photographic film, they do not typically interact with fluorescent materials in the same way that ultraviolet radiation does. Infrared radiation, meanwhile, primarily affects heat-sensitive devices rather than photographic film or fluorescent substances. Thus, ultraviolet radiation is the type that interacts effectively with both photographic film and fluorescent materials.