Description: This scientific experiment for children demonstrates that tension on top of the water will float a needle. When dish detergent is added to the water, the detergent breaks up the tension of the water and the needle will sink.
Goals: To demonstrate that tension on the surface of water supports objects, but when the tension is broken
(adding dish soap) the needle will sink.
Objectives:
1.
To learn that the surface of the water has tension and will float a needle.
2.
To learn that when the surface tension is broken, the needle will sink.
Materials:
 Water
 Bowl


Newspaper
 Sewing needle
Liquid detergent
Procedure:
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.
Resource: www.familyeducation.com
Alice K. Dolu, WVU Extension Agent, 4-H Youth Development – Marshall County
April 20 Page
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