| A | B |
|---|
| transparent | Materials that allow light to travel through them. |
| amplitude | The amount of energy in a sound wave. |
| eardrum | The thin tissue between the ear canal and the middle ear. |
| opaque | Materials that allow NO light to travel through them. |
| translucent | Materials that alllow SOME light to travel through them. |
| decibel | A unit used to measure the loudness of sound. |
| echo | A reflected sound. |
| noise pollution | Any sound that causes problems for people. |
| reflection | When light bounces off an object. |
| pitch | How high or low a sound is. |
| vibrate | To move back and forth rapidly. |
| refraction | When light bends through transparent material |
| convex lens | A lens that is thicker at the cetner than at the edges; light comes to a point. |
| vocal cords | Folds of thin muscle tissue in the throat. |
