Thursday, May 17, 2012
Magic Rising Water
Demonstrate air pressure with this magical tabletop experiment from Steve Spangler. Pour 9 oz. of water (food coloring optional) into a shallow dish. Place a candle in the center of the dish and light it. Put a glass over the candle and watch water rise right before your eyes! What's happening? The flame heated up the air trapped in the glass, causing the flame to go out. Once the flame goes out, everything cools down. The cool air (gas) acts as a "vacuum," causing the water to rise! Once you lift the glass up, the water falls back into place. Besides air, talk to students about thermal energy. Is the glass an insulator or a conductor of heat?