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Floating Needle

Materials

• Water
• Bowl
• Newspaper
• Sewing needle
• Liquid detergent

Directions

1. Cut out a piece of newspaper about two inches square.
2. Fill the bowl with water and float the newspaper on the surface of the water.
3. Place the needle in the center of the newspaper.
4. Carefully push the edges of the newspaper down into the water.
5. As the newspaper gets wet and sinks, it will leave the needle floating.
6. Now add a drop of liquid detergent to the water at the edge of the bowl.
7. Notice how the needle quickly sinks to the bottom.

Note: Surface tension made it possible to float the needle on water. The needle was supported by the water. The detergent caused a break in the surface tension around the needle and it sank.