Across
- 3. The number of protons in the nucleus of an atom.
- 6. Radiation consisting of fast-moving electrons.
- 10. Radiation that can remove electrons from atoms.
- 11. Unit used to measure the activity of a radioactive source.
- 13. A detector used to measure ionising radiation.
- 15. When radioactive material gets inside or onto an object or person.
- 16. Exposure to radiation without radioactive material being transferred.
- 18. A neutral particle found in the nucleus of an atom.
Down
- 1. The time taken for the activity of a radioactive source to halve.
- 2. Highly penetrating electromagnetic radiation.
- 4. The total number of protons and neutrons in a nucleus.
- 5. Radiation that is always present from Earth and space.
- 7. The rate at which a radioactive source decays.
- 8. Strongly ionising radiation with low penetrating power.
- 9. How easily radiation passes through materials.
- 10. Atoms of the same element with different numbers of neutrons.
- 12. A negatively charged particle that moves around the nucleus.
- 14. A positively charged particle found in the nucleus.
- 17. The smallest unit of an element, made of protons, neutrons and electrons.