Resonance

A five year old demonstrated this to me on a front porch with a jelly jar. The jar did not fall off the railing but I do suggest using a wine glass. The cheaper, the better it will resonate.

Use a wine glass because you can hold the glass by the stem. When I taught school, I got quite a collection at yard sales. Do warn children to not go home and use mom's fine crystal. One child broke an expensive wine glass at home doing this.

Directions:
1. Partially fill wine glass with water.
2. Dip index finger in water.
3. Rub the rim of the glass with finger until the glass vibrates. It makes a pleasant sound.

4. You can have students compare the sound of different wine glasses and different water levels.