Across
- 2. Curving outwards like the outside of a ball.
- 10. Waves A band of electromagnetic waves of lowest frequency used for radio and TV signals.
- 12. Allowing light to pass through so that objects behind the surface can be seen clearly.
- 15. The height of the crest or the depth of the trough.
- 18. The turning or bending of light when passing from one medium into another of unequal density.
- 21. Curving inwards like a bowl.
- 22. A curved piece of transparent material, usually glass or plastic. Light rays bend as they pass through the lens.
- 23. Rays The electromagnetic waves of the highest frequency.
Down
- 1. Light rays that are coming together at a focal point, passing through convex lens.
- 3. Point The spot where a ray of light meets after it has passed through a convex lens.
- 4. A radio wave having a short wavelength and high frequency; used in microwave ovens; telecommunications satellites and other applications.
- 5. The band of electromagnetic radiation above visible light and below x-rays.
- 6. Allowing a small amount of light to pass through so that objects behind the surface can be seen, but not as clearly.
- 7. Light The band of electromagnetic radiation that we can see. It frequencies are above infrared and below ultraviolet.
- 8. Spreading out.
- 9. The number of entire cycles completed by a vibrating object in a unit of time; usually given in cycles per second, or hertz.
- 11. Heat radiation; anything that is warmer than its surrounding emits infrared rays.
- 13. The arrangement according to wavelength of visible, ultraviolet, and infrared light.
- 14. Electromagnetic radiation having a very short wavelength. It can penetrate substances such as skin and muscle.
- 16. Not allowing any light to pass through.
- 17. The high part of a wave.
- 19. A clear, protective outer layer of the eye.
- 20. of reflection The angle at which a ray of light reflects off a surface. It is formed by the normal and the reflected ray.