Many students are confused by the nature of radiation in general and some think it is artificial
This has been observed in the following ways:
- The radiation with which food is treated was seen as coming from "special substances". Others expected the radiation to originate from the "fission of certain molecules" or from "a blue spiral in a tub of water".
- Students appeared to have difficulties in viewing radiation from building materials as natural.
You may wish to start a class discussion about radiation in various contexts, like those described above, and listen out for your students' ideas.
Resources to Address This
Demonstrate the existence of background radiation with different detectors. The different sources of this background can then be discussed, showing that nearly all of it is from natural sources, including rocks, building materials and food.
Students can also analyse radiation from collected dust, typical doses and whether they should be worried about the size of their annual dose.View Resource
Outline the discovery of ionisation radiation with this background information, pointing out that it was discovered and explained long before the construction of nuclear power plants.
Discuss the natural radioactive materials used in early experiments and the discovery of radiation from space.View Resource
Use these materials to discuss the discovery of radioactivity by Henri Becquerel, outlining his experiments and their significance.
Emphasize his use of naturally radioactive materials in his experiments and his logical approach in proving that an invisible radiation existed.View Resource
- Eijkelhof, H. M. C., () Radiation and risk in physics education, PhD thesis.