Across
- 1. scientist who first showed the nucleus had a concentrated mass and charge
- 3. least penetrating radioactive emission
- 4. particle which has a mass of 1 and a charge of +1
- 8. time required for a quantity to reduce to half of its initial value
- 10. radioisotope found in smoke detectors
- 13. least penetrating radioactive emission
- 16. most used radioisotope in diagnostic imaging
- 18. represented by lambda in decay calculations
- 20. when electrons lose energy and fall to lower shells
Down
- 2. scientist who first showed the atom was made of smaller things
- 5. if it has an unstable ratio or protons and neutrons
- 6. the effect of a material emitting electrons when exposed to light
- 7. name of the constant which links E with f
- 9. a fundamental particle with a relative mass of 0.0005u
- 11. your physics teacher's first name
- 12. the units when you divide the energy in joules by 1.6x10-19
- 14. used to test the integrity of pipeline welds
- 15. a fast-moving electron
- 17. the length of a wave
- 19. the fundamental particles that make up protons & neutrons