Sound Travels Through Materials

Objectives

To understand that sound travels better through certain materials than the air.

To consider variables which could make a difference to a sound.

Resources

Lined paper | Tin cans | String | Pool of water | Small pebble

Today's Lesson

Main Activity

Have you ever heard a plane in the sky above? The plane is the source of sound. Sounds travel through the atmosphere in waves from the source to our ears.

Remind your child of the learning from Week 13, Lesson 1. An effective way to model the way sound travels is to drop a small pebble into a pond of water and watch the waves ripple from the point of entry, spreading outwards. Although we cannot see this, sound travels through the atmosphere in the same way until it reaches our eardrums, causing them to vibrate and resulting in our ability to hear the sound.

Help your child to make a string telephone using the instructions document and test how well sound travels along the string. Then challenge your child to consider ways in which the sound could be changed, and to experiment with this.

📄 CREATE - Make a String Telephone craft instructions

For example: by changing the thickness of the string; changing the length of the string; changing the material of the string; changing the types or sizes of the cups or containers.

Ask your child to draw their own table to record their results. If they need help with this, suggest using a table such as the one below:


	Short string length (____ cm)	Medium string length (____ cm)	Long string length (____cm)
Description of the sound (pitch / volume)
Variables I kept the same
Conclusion	Example: The shorter the string, the higher the pitch. The longer the string, the lower the pitch.

What to Notice

Citations

[1] www.youtube.com