Refraction

4. Vibrations in the particles of a solid, liquid or gas, which are detected by our ears and ‘heard’ as sounds.
8. The time taken for one complete wave to pass a point. It is measured in seconds.
9. The size of vibrations or the maximum distance a particle moves away from its resting position when a wave passes.
11. A group of waves that all travel at the same speed in a vacuum, and are all transverse.
12. A way of transferring energy or information. Many waves travel when particles pass on vibrations.
13. A wave where the vibrations are at right angles to the direction the wave is travelling.

1. Vibrations in the rocks of the Earth caused by earthquakes or explosions.
2. A wave where the particles vibrate in the same direction as the wave is travelling.
3. Any substance through which something travels.
5. The unit for frequency.
6. The speed of an object in a particular direction. Usually measured in metres per second (m/s).
7. The number of vibrations (or the number of waves) per second.
10. The distance between a point on one wave and the same point on the next wave.