Two Tuning Forks Share a Note

1. Two Tuning Forks Share a Note Materials: Two matching tuning forks/resonance boxes What you do: Strike one fork, bring it near the second, then damp the first. What students see: The second fork continues sounding. Question: How did the second fork start vibrating? 2. Slinky Waves Two Ways Materials: Large slinky What you do: Show side-to-side and push-pull pulses. What students see: The slinky carries transverse and longitudinal waves. Question: Does the slinky itself travel down the room? 3. Cup Telephone Distance Test Materials: Two cups; taut string What you do: Speak through the cup with string taut, then loose. What students see: Sound is much clearer with taut string. Question: Why does a loose string work poorly?

Predict → observe three demonstrations → compare what changed → choose independent activity station → cleanup/share. Guiding questions: Question: How did the second fork start vibrating? Question: Does the slinky itself travel down the room? Question: Why does a loose string work poorly?