Across
- 5. light pulses transmitted along these (5,6)
- 7. penetrating radiation which can cause damage to body tissues, useful to kill cancer etc.
- 9. objects that absorb uv waves and emit the energy as visible light
- 12. penetrate our body and provide a valuable way for doctors to diagnose illness or damage to our bodies
- 13. electromagnetic waves are
- 15. repeating the results reduces the effect of errors, this is called ________
- 18. hot objects emit this, used in efficient lamps
- 19. radio waves transmitted over long distances by being reflected off this (layer in the earth's upper atmosphere)
- 20. used to send ____ and television signals from transmitters to homes, terrestrial as they go across ground
- 21. _______ wavelength at highest energy
Down
- 1. used to see
- 2. used for satellite communication, satellite television, mobile phone networks through tall aerial masts, cooking, heating
- 3. electromagnetic waves can travel through a
- 4. ________ wavelength at lowest energy
- 6. heating from electrical heaters, cooking in ovens, cameras for photographs at night, remote controls
- 8. the required practical of this topic to see the emission of _________
- 10. _______ frequency at lowest energy
- 11. wave formed by a change in the nucleus of an atom, when this is emitted the nuclear store decreases
- 14. control variables ensure ________
- 16. the speed that they travel at in a vacuum
- 17. _____ frequency at highest energy