Bouncing bubbles

You will need:

• A measuring cup
• A transparent bottle
• Cotton gloves
• Dishwasher detergent
• Water
• Straws
• Bamboo chopsticks

Step-by-step instructions:

1. Use a 50cc measuring cup to measure out 30cc of dishwasher detergent and pour it into the transparent bottle.
2. Use a 150cc measuring cup to measure out 120cc of water and again pour it into the transparent bottle.
3. Use the bamboo chopsticks to stir the resulting mixture slowly and evenly.
   (This is to avoid generating small amounts of foam that may affect the results of the experiment.)
4. Try using the straw to blow bubbles.
5. Wear a cotton glove on one of your hands.
6. Use the straw to blow a bubble into the air with a straw.
7. Gently touch the bubble with the cotton glove and the bubble will bounce up and down.

※ REMEMBER!The ratio of the dishwasher detergent to water should be 1:4

How it works:

The main reason why a bubble will burst is because its surface (the bubble’s film) has been damaged. Take a balloon as an example. If you poke the balloon with your finger, it will not burst. However, if you poke the balloon with a needle, it will burst right away. This is because the needle is sharp, meaning that it can damage the surface of the balloon. As soon as a hole is made in the balloon’s surface, the balloon will burst, as a result of the tension around the hole.

When your hand touches the surface of the bubble’s film, the bubble will burst like a balloon being poked by a needle, because your hand is hard. The fibers of the cotton glove, however, are relatively soft, much like soft springs. As a result, the bubbles bounce up and down, instead of immediately bursting.

＊Resource come from: NTCU Science Game Lab.