Across
- 2. A type of mirror that is curved outward on at least one side so its middle is thicker than its edges, bending light towards a focal point
- 4. A type of mirror that has a flat reflecting surface
- 7. A wave that changes direction as it travels from one material to another
- 8. Two words, cells that are sensitive to low-light levels
- 10. A type of mirror that is curved inward
- 11. Allows almost all to pass through and forms a clear image
- 13. Two words, longest wavelength, lowest frequency, longer than 30cm
- 14. Does not allow light to pass through
- 15. Any reflecting surface that forms and image by regular reflection
- 17. Two words, a narrow beam of light that travels in a straight line
- 18. Two words, anything that emits light
- 19. Two words, black light, higher energy levels make them harmful to living things
- 20. A type of mirror that is curved inward on at least one side so its edges are thicker than its middle, bending light outwards
- 21. Two words, shorter than microwaves but longer than visible light, all vibrating particles emit these
Down
- 1. Two words, cells that enable the observation of color
- 3. Two words, ROYGBIV
- 5. A transparent object with at least one curved side that causes light to change direction
- 6. Allows most light to pass through but forms a blurry image
- 9. Occurs when light waves traveling in one direction are made to travel in many directions
- 10. A type of mirror that is curved outward
- 12. An opening into the interior of the eye at the center of the iris
- 13. A layer of special light-sensitive cells in the back of the eye
- 16. The colored part of an eye