Across
- 4. Sound with a frequency above the threshold of human hearing
- 5. Cosmic rays are the biggest source of __________ radiation
- 8. Two objects with opposite charges do this
- 9. A heart does this when we use a defibrillator
- 10. Two objects with the same charge do this
- 12. The yellow and green wire in a plug
- 13. This causes electrons to move when two objects are rubbed together
- 14. The charge of a neutron
- 15. The ______ number tells you the number of protons in an atom
- 16. A safety feature in a plug
- 17. ____ life - the time taken for the activity of a radioactive source to decrease by half
Down
- 1. The ____ number tells you the total number of protons and neutrons in an atom
- 2. A charged atom
- 3. An electrostatic __________ is an industrial use of electrostatics
- 6. The charge on a beta particle
- 7. The charge of a proton
- 11. The colour of the live wire in a plug
- 14. Radiation comes from this part on an atom
- 15. This type of radiation is a helium nucleus