Objective

Use a classic children’s game to demonstrate the ability of sound to travel through an object.

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Project Details

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Materials

• Paper or plastic cups
• Scissors
• String
• Tape
• A friend

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• Using the point of the scissors, poke a hole in the middle of the bottom of each cup.
• Stand a few feet away from a friend and talk to each other in normal voices. Keep moving apart until you can no longer hear each other well enough to have a conversation.
• Hold one of the cups up to your mouth and speak into it while your friend listens into the other. Can you hear each other?
• Next cut a length of string long enough to stretch between you and your friend when you could no longer talk to each other.
• Poke the ends of the string through the holes in the bottoms of the cups and tape the ends securely to these bottoms.
• Hold onto one cup and have your friend hold onto the other and walk away until the string is taut.
• Talk into one cup while your friend holds the other cup over her ear. Switch. Now can you hear each other through the cups? 
• Discuss the possible reason for why attaching the cups with the string allowed you to each other.

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