Problem Solving with Sound

Problem Solving with Sound — How can sound move through different types of materials?

Experiment 1:

Materials:

1. Two plastic cups (can be recycled materials, such as a small yogurt or sour cream container)
2. String – about 10 ft (or fit to the size of your home)
3. Metal hanger (optional)
4. Spoon (optional)

Preparation (for adults):

1. Punch a small hole in the bottom of each cup
2. Pull the string through each cup to make cup and string telephones

What to do:

1. Have one person at each end of the cup and string telephones
2. Hold the string tight and one person listens while the other whispers into the cup.  What do you hear?
3. Hold the string loose and one person listens while the other whispers into the cup.  What do you hear?
4. Next have each person listen at each end of the cup and hold the string tight.  Have another person pluck the string.  What do you hear?
5. Hang a metal hanger on the string while two people listen.  Lightly tap the hanger with the spoon.  What do you hear?
6. How does the sound travel to your ear?  
7. Draw a picture to show how the sound moves to your ear.

Experiment 2:

Materials:

• 6 pieces of string – about 3 ft each
• Hangers – 1 metal, 1 plastic, 1 wooden (with a metal top is okay) 
• Spoons – 1 metal, 1 plastic, 1 wooden

Preparation (for adults):

• Tie each string to each bottom end of the hangers, like this

What to do:

1. Using one hanger at a time, wrap one end of the string around your pointer finger on each hand
2. Place your fingers in your ears
3. Have someone else use each type of spoon and lightly tap the hanger as it hangs in front of you.  Try not to let the hanger touch your shirt.  What do you hear?  Is the sound different or the same with each spoon?
4. Try each hanger with the different spoons.  What sounds the same?  What sounds different?
5. How does the sound travel to your ears?
6. Draw a picture to show how sound travels.