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Try this experiment with carbonated water. Carbonated water has carbon dioxide dissolved in it. When it’s in an unopened bottle, this carbon dioxide is under pressure and remains in solution. When you ...
When you vocalize, you cause air molecules to vibrate. These vibrating molecules strike the rubber balloon membrane. The membrane vibrates, causing the mirror to wiggle in turn. The laser light ...
Make waves without getting wet.When you move your hands together, you make a half a wave on the Slinky. The middle of the Slinky is an antinode, a point of maximum motion, while the hand-held ends are ...
If you reach up and feel around your eye, you’ll feel the bone of your skull. There’s fat surrounding your eyeball to keep it from bumping up against the bone and getting bruised. In the cow’s eye ...
The Sun and moon aren’t really the same size, of course: the Sun is 400 times the diameter of the moon. But it’s also 400 times farther away from us, and this relationship between size and distance ...
Download the PDF file containing the cipher wheels. Copy and cut out the two wheels. Place the smaller wheel on top of the larger wheel and rotate them so your "key letter" on the small wheel is ...
De-shell the eggs by placing them in a large container so that they touch as little as possible. Add vinegar to cover the eggs (see photo below), and cover the container. Allow the eggs to sit for 24 ...
Make three Roto-Copters for each person. Use a marker to draw a 1-foot circle on a piece of newspaper. Put a cereal bowl in the middle of the circle. The circle is the target area and the bowl is the ...
Density columns are made by layering liquids of different densities. If neighboring layers are insoluble with each other, the column will stay in separate layers unless disturbed. The problem arises ...
One of the most exciting exercises I ever did as a kid was to make a scale model of the Solar System. Most of the pictures in my books made the distance between planets seem small and easy to travel.
Every cell in your body needs to take in nutrients, oxygen, and raw materials and export wastes and other substances—but it’s not just a random traffic jam! A cell membrane (also called a plasma ...
Speed up your spin.Newton found that an object in motion tends to remain in motion, in a straight line and at a constant speed, unless it is acted upon by a net force. Today, we call this observation ...