Force
Forces and Motion

Bead Fountain

Enrichment Activity for 5-11 11-14

What you need

  • A long string of beads
  • A circular glass container
  • A table

Instructions

  1. Coil the beads carefully into the container so you have layers of circles, one on top of the other
  2. Lift the container high. Take the free end of the beads and flick it quickly over the side of the container

Results and Explanation

All the beads should “flow” out of the container without help. When they’re moving fast they should even jump higher than the rim of the container.

The weight of the falling beads creates a tension in the chain that acts to pull the rest of the beads in the container up and over the rim. But not all physicists agree on the exact reason!

These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.

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