Activity Overview
Convince your audience that you can teach a cup of water to obey basic commands. This Well Trained Water tricks is relatively easy to master and fun to perform. Be sure that you perform this trick over a sink or a bucket or perform it outside, as there will be spillage of water in this trick.
This trick combines magic with science. When you cover the puncture in the cup, you create a partial vacuum inside of the cup. Air pressure on the outside of the cup and paper keep the paper stuck to the cup until you release your thumb from the hole and break the vacuum seal which lets the air pressure move into the glass.
Materials Needed
- A piece of paper
- A paper or plastic cup
- A sharp pencil
- Water
How to Do It
- Use a sharp pencil to punch a hole on the side of the cup near the bottom.
- Hold the cup upright in your hand with your thumb covering the hole.
- Fill the cup half filled with water.
- Place a piece of paper over the top of the cup and cover it firmly with the palm of your hand.
- Say a few magic words and give the water instructions to stay in the cup when you flip it over.
- While holding your thumb continuously over the hole in the cup and with your other hand holding the paper in place, flip the cup over.
- Carefully remove your hand from the paper only. The water should stay in the cup as long as your thumb is covering the hole.
- Use some fancy magic words and instruct the water to release. At this time discreetly remove your thumb from the hole in the cup and the paper and water will immediately drop.
