Across
- 4. A material through which sound travels.
- 8. The bouncing back of a wave from a surface.
- 9. A reflected sound heard again after the original sound.
- 12. A wave that transfers sound energy through a medium.
- 13. A movement that starts a wave.
- 14. A space with no matter or particles.
- 15. A form of energy produced by vibrations that we can hear.
- 16. The number of vibrations per second.
- 17. A region in a sound wave where particles are close together.
- 19. A wave in which particles vibrate in the same direction as the wave travels.
Down
- 1. The movement of energy from one particle to another.
- 2. The rate at which sound travels through a medium.
- 3. A boundary where a wave can reflect.
- 5. Anything that has mass and takes up space.
- 6. How loud or quiet a sound is.
- 7. The size or height of a vibration.
- 8. A region in a sound wave where particles are spread apart.
- 10. A repeated back-and-forth movement of particles.
- 11. A tiny unit of matter that makes up substances.
- 18. How high or low a sound seems.