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Chemistry

[- Air -]The Air around us is not weightless. In fact, it can be weighed almost as accurately as iron or lead. A column of Air 1 inch square and 600 miles high, for instance, weighsapproximately 15 pounds, about twice as much as an average newborn baby. This weight is what creates the phenomenon known as "atmospheric pressure."

[- Elements -]Ten of the 105 known Elements had beendiscovered and were in use in prehistoric times: gold, silver, lead, iron, copper, zinc, tin, sulfur, carbon, and mercury. The largest individual contribution to the table of Elements was that of thenineteenth century English chemist Sir Humphrey Davy, who identified boron, barium, calcium, potassium, sodium, and strontium in 1807 and 1808. He also demonstrated that diamonds are composed of purecarbon and discovered the hilarious properties of nitrous oxide --"laughing gas."

[- Sodium -]If the chemical Sodium is dropped in water and a match is taken to the mixture, it will immediatelyand violently ignite. If Sodium is immersed in a pot of kerosene, however, it will not burn at all.

Physics

[- Sound -]Sound travels fifteen times more swiftly through steel than through air.[- Theory of Relativity -]According to the Theory of Relativity, the mass of an object increases with its velocity. In nonscientific terms, this means that things get bigger as they move faster. Theprocess has been demonstrated in laboratories. In several experiments, objects accelerated to 86 percent of the speed of light have doubled in weight. The theory also postulates the ratherincomprehensible notion that given enough speed, an object will become as large as the universe itself.

[- Volume -]A pipe 2 feet in diameter will allow four times more fluid to pass through it than a pipe 1foot in diameter-the Volume of a pipe varies as the square of its diameter.

[- Water Pressure -]If you punch a series of holes in a paper cup filled with Water, the Water will squirt out farthest...