Category Archives: Uncategorized
Why do we feel pain when we are hurt?
Heat of the candle flame sends pain messages to the brain through long threads of nerve cells. Consider yourself lucky that you can feel pain. Pain is your protector. It warns of possible danger to the body. If you did not feel pain from touching something hot, you might not jerk your hand away in …
How are bricks made?
The ordinary bricks that a bricklayer uses to build a brick house are usually made from clay that is baked in an over. To make bricks, he brick makers grind the clay and mix it with water. Some sand is added, too. A brick making machine pushes the soft clay through a hole to form …
Why do we perspire?
The sweat glands help keep you cool in the summer. When we get very warm, little beads of water called sweat form on our skin. Perspiration is a quick method of cooling off the body. You can test this by wetting your hands and waving them rapidly. The water evaporates quickly and makes your hands …
How are natural diamonds formed?
Diamonds are formed in dying volcanoes. As the hot lava cools, great pressure and heat act on the carbon found in the lava and change the carbon into diamonds. You may know that a diamond is simply a crystal of common carbon, of which coal is largely formed. Diamonds were formed millions of years ago in …
What does ‘dew point’ mean?
The dew point is the temperature at which moisture in the air begins to condense. Perhaps the air doesn’t seem damp at all. It does, however, have many tiny, invisible bits of water moving about in it. We call these tiny specks of moisture “water vapor.” Cold air cannot hold as much moisture at warm …
Why is the season of autumn called fall?
Autumn is the season of the year that comes between summer and winter. For those of us who live where there is a marked changed of season, we know it’s autumn when the leaves change color and the crisp air pinches our cheeks. Americans often call this season “fall” because it is the time of …
How does the anchor hold the ship?
An anchor is a heavy weight that is used to hold a boat in place in the water. In olden days, sailors used large stones or other heavy objects which held the boat in place merely by their weight. But as ships became larger, iron anchors were made with flukes, or “hook,’ that dug into the …
Where do freckles come from?
Freckles are the small, crown spots that dot the skin of some people. There are certain cells in your skin which produce a dark pigment, or coloring matter. This pigment, called “melanin,” gives the brown color to the skin. How much of this dark pigment you have usually depends on how much of it your …
What do the numbers in the zip code mean?
The post office can deliver mail more quickly because of the zip code. There is a five-number zip code for every address. Here’s how it works. The United States and its possessions are divided up into 10 large parts. Each part has a number between 0 and 9. Suppose the zip code on the letter …
