Across
- 3. The low part of a wave
- 4. The bouncing of light off a surface
- 7. The distance between crests
- 9. How high or low a sound is
- 11. The bending of light around edges of objects
- 14. Stored energy
- 15. Material that allows most light through it
- 17. The ability to cause change in matter
- 18. The amount of times something occurs
- 20. Energy of heat
Down
- 1. A measurement of the loudness of sounds
- 2. Material that allows some light through it
- 5. The high part of a wave
- 6. The bending of light between object's surfaces
- 8. The energy of motion
- 10. Material that doesn't allow light through it
- 12. The energy of the Sun
- 13. A disturbance that carries energy through matter
- 16. Energy produced by nuclear reactions
- 19. The distance from the crest to the trough