Jumping Coin with Bernoulli’s Principle

Materials: ★☆☆ Easy to get from supermarket or hardware store
Difficulty: ★★☆ Can be done by science teachers
Safety: ★☆☆ Minimal safety procedures required

Categories: Motion, Pressure and Fluids

Alternative titles: Coin Jump into Cup

Summary

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.

Procedure

  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:


Variations

Safety Precautions

Questions to Consider