Electroscope - What's your (electrical) sign?

Electroscope   What's your (electrical) sign?    A commonly available brand of plastic tape can gain or lose negatively charged electrons when you stick it to a surface and rip it off. By suspending pieces of tape from a straw, you can build an electroscope, a device that detects electrical charge. A plastic comb will enable you to identify whether the pieces of tape are positively or negatively charged.    4 plastic drinking straws with flexible ends. 2 plastic 35 mm film cans. Enough modeling clay to fill the film cans halfway. A...

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Electrical Fleas - Start your own electric flea circus

Electrical Fleas   Start your own electric flea circus!    You're probably familiar with some of the effects of static electricity: Static electricity makes the sparks when you comb your hair on a cold day, and it makes balloons stick to the wall at a birthday party. In this Snack, static electricity makes electric "fleas" jump up and down.    A sheet of acrylic plastic or other clear plastic (about 1 foot [30 cm] square and 1/s inch [3 mm] thick). A piece of wool cloth or fur. 4 supports about 1 to 2 inches (2.5 to 5...

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Eddy Currents - A magnet falls more slowly through a metallic tube than it does through a nonmetallic tube.

    Eddy Currents   A magnet falls more slowly through a metallic tube than it does through a nonmetallic tube.    When a magnet is dropped down a metallic tube, the changing magnetic field created by the falling magnet pushes electrons in the metal tube around in circular, eddy-like currents. These eddy currents have their own magnetic field that opposes the fall of the magnet. The magnet falls dramatically slower than it does in ordinary free fall in a nonmetallic tube.    A cow magnet or neodymium magnet. ...

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Duck Into Kaleidoscope - Make multiple images of yourself.

Duck Into Kaleidoscope   Make multiple images of yourself.   Duck Into Kaleidoscope will create hundreds of images of - whatever you place inside it. The basic kaleidoscope is a triangle, but mirror tiles can beformed into other shapes and angles as well.    6 mirror tiles measuring 1 x 1 foot (30 x 30 cm). (Or use plastic mirrors from a plastic supply house.) Duct tape. 3 pieces of sturdy cardboard measuring 1 x 2 feet (30 x 60 cm). Adult help. (30 minutes or less) Place the six mirror tiles...

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Drawing Board - A pendulum moving in two directions creates beautiful designs.

Drawing Board   A pendulum moving in two directions creates beautiful designs.    The Drawing Board consists of a marking pen that remains stationary and a platform that swings beneath the pen, acting as a pendulum. As the platform swings, the pen marks a sheet of paper that is fastened to the platform, generating beautiful repetitive patterns, which grow smaller with each repetition. These colorful designs contain hidden lessons in physics.    Make Your Own Version: A ruler. One 4 x 4 x 12 inch (10 x 10 x 30 cm)...

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