This demonstration shows how a coin can appear to jump into a cup under its own power. By blowing in a specific way, air pressure differences created by the Bernoulli principle cause the coin to lift and move into the cup.

1. Place a coin on a flat surface near the rim of a lightweight cup.
2. Hold the cup sideways, positioned just above and slightly in front of the coin.
3. Blow steadily between the coin and the cup.
4. Observe as the coin lifts and jumps into the cup, appearing to move on its own.

Mysterious Coin Jumps Into Cup On Its Own - The Action Lab:

• Try different coin sizes and weights to see which works best.
• Experiment with different cup shapes to find the most effective setup.
• Test how blowing speed and angle affect the coin’s motion.

• Use a clean, dry surface so the coin doesn’t slip unexpectedly.
• Wash hands after handling coins, as they may carry germs.

• Why does the coin move toward the cup instead of away? (Blowing creates faster-moving air between the coin and the cup, lowering the pressure there. Higher surrounding air pressure pushes the coin toward the low-pressure region and into the cup.)
• How does this demonstrate the Bernoulli principle? (It shows that faster air movement reduces pressure, allowing external pressure to move objects.)
• What real-world examples use the same principle? (Airplane wings, atomizers, and some sports ball curves all rely on Bernoulli’s principle.)