Refraction Crossword Across Down 1. Light deviates ******* the normal when it passes from air to perspex 3. Clear plastic 6. Difference in direction of two lines 7. Initial ray 9. The ***** of light changes when enters glass 10. This can undergo refraction 12. Light deviates **** from the normal when it passes from glass to air 13. The speed of light ********* when it enters perspex 15. The speed of light ********* when it leaves perspex 16. Line at 90 degrees to a surface 2. Name of ray after refraction 4. Angle in degrees between the normal and a surface 5. Clear substance used in windows 7. Initial angle 8. When light changes direction or speed on entering perspex 11. The path taken by light 14. A word that means change direction 17. Refraction can occur when light passes from *** to water