Across
- 4. A line 90 degrees from the area of reflection
- 7. Rate which something occurs over time
- 10. Straight line which streams from the sun or other sources of light
- 11. Measurement of how loud something is
- 12. Something which curves outwards
- 14. The distance from rest point to the trough of the wave
- 16. The distance from the crests of a wave
- 17. Pupil is in the centre of this
- 18. Unit of energy
- 20. Changes size to let light into eye
Down
- 1. Skin in the ear which is stretched tight and which vibrates when sound hits it
- 2. Something which curves inwards
- 3. Return of light/ sound from a surface
- 5. Bending of a ray when it passes through a medium
- 6. Comes from the sun
- 8. Clear protective layer for the eye
- 9. Disturbance when a transfer of energy occurs
- 13. Ability to do work
- 15. Light sensitive membrane at back of eye
- 19. Vibrations that is heard when it reaches an ear