# Hands-On Science

physics

## Straw Pipe

Make music with drinking straws and learn how sound works.

## Materials

• Eight straws
• Scisscors
• Ruler
• Masking tape
• Pen or marker

## Directions

1. Measure and cut the straws into these lengths: 19.5 centimeters, 17.0 cm, 15.5 cm, 14.5 cm, 13.0 cm, 11.5 cm, 10.0 cm, 9.5 cm.
2. Label the longest straw #1, the next longest straw #2, and so on. The smallest straw should be labeled #8.
3. Tape the straws together in order from longest to shortest. You can use small pieces of straw (about 2 cm long) as spacers between the longer straws. This is called a pan pipe.
4. Hold the pan pipe vertically below your lips, with the uneven ends pointing down. Blow across the tops of the straws as though you are blowing across the top of a pop bottle.

Try playing one of the songs below, or make up your own songs. Remember: 1 is the longest straw and 8 is the smallest straw.

Twinkle, Twinkle Little Star
11 55 66 5 44 33 22 155 44 33 2 55 44 33 211 55 66 5 44 33 22 1

Jingle Bells
333 333 35123444 4433 3355421

Mary Had a Little Lamb
3212333 222 3553212333 322321

## What's happening?

As you blow across a straw, the air in the straw vibrates. These vibrations travel outward and reach our ears sounding like the notes of a scale. You can change the pitch (the perceived highness or lowness of a sound) by changing the length of the straw. A long straw produces a low note. A short straw produces a high note.

## Vocabulary

Vibrate
To move rapidly back and forth

Pitch
How high or how low a sound made by a particular instrument will sound to the ears.  Pitch is determined by the frequency of the sound waves.

Frequency
How often a sound wave goes by

## Background information

As you blow across a straw, the air in the straw vibrates. These vibrations travel outward and reach our ears sounding like the notes of a scale. You can change the pitch (the perceived highness or lowness of a sound) by changing the length of the straw. A long straw produces a low note. A short straw produces a high note.