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Watch water boil at room temperature. The temperature at which water boils depends on pressure. You can demonstrate this by dramatically lowering the pressure on a water-filled plastic syringe at room ...
Use your voice to transform laser light into dazzling patterns. By humming, singing, or talking into the Vocal Visualizer, you’ll be able to see sound as vibration (or pressure waves) and experience ...
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 ...
Here’s a cow’s eye from the meat company. The white part is the sclera, the outer covering of the eyeball. The blue is the cornea, which starts out clear but becomes cloudy after death.
A solar eclipse happens when the moon passes between the Sun and Earth, casting a shadow on Earth that either fully or partially blocks the Sun's light in some areas.
Substitution ciphers and decoder rings We use substitution ciphers all the time. (Actually, substitution ciphers could properly be called codes in most cases.) Morse code, shorthand, semaphore, and ...
Use a giant cell—a de-shelled chicken egg—to explore the comings and goings of cellular substances.
This simple paper toy spins through the air like a mini-helicopter ...
This density column always returns to its original three layers.
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.
Soap films can behave like membranes. 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 ...
You’ve probably seen an ice skater spinning on the tip of one skate suddenly start to spin dramatically faster. A diver or gymnast may also suddenly flip or twist much faster. This speeded-up rotation ...
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