Coupled Pendulums

1. Coupled Pendulums Materials: 2 pendulums hanging from a shared flexible support What you do: Start only one pendulum. What students see: Motion slowly transfers to the other. Question: How did the second pendulum start moving? 2. Static Butterfly Wings Materials: Paper butterfly; cardboard; balloon What you do: Charge balloon and move it above light paper wings. What students see: Wings lift toward balloon without contact. Question: What invisible force is lifting the wings? 3. Static Balloon Bends Water Materials: Charged balloon; thin steady stream of water What you do: Rub balloon on fleece and bring it near—not touching—the water stream. What students see: The water stream bends toward the balloon. Question: How can the balloon pull water without touching it?

Predict → observe three demonstrations → compare what changed → choose independent activity station → cleanup/share. Guiding questions: Question: How did the second pendulum start moving? Question: What invisible force is lifting the wings? Question: How can the balloon pull water without touching it?