How does a blimp stay in the air?

A blimp is an airtight bag that is able to rise in the air because it is filled with light gases.  A blimp is a small, balloon-like airship.  Unlike the heavier-than-air airplane, the blimp remains aloft because it is lighter than air.  

It needs only small motors to push it forward.  Blimps are descendants of the simple balloon. The blimp's lift comes from a lighter-than air gas that raises the blimp in the same way a balloon is lifted.

A balloon rises because the gas inside the balloon is much lighter than the air round it, and so it floats in the atmosphere, in much the same way a ship floats on water.  The gas inside the blimp expands and fills out the blimp.  Its gasbag has no framework inside, and collapses when the gas is taken out.

Some airships, such as the dirigible, have an inside framework that supports the sides, and do not depend on the pressure of the lifting gas to maintain their shape.  During World War II, blimps protected ships by spotting enemy submarines.  

They were also used for observation, photographing enemy positions and for rescues at sea and on land.  Today, blimps with signs painted on their sides are used mostly for advertising and sightseeing. – Dick Rogers

What were the Egyptian pyramids built for?

The Egyptian pyramids were built as tombs for ancient Egyptian kings.  Perhaps the first thing you would look for if you visited the United Arab Republic would be the ancient Egyptian pyramids near the Nile river.  

Each pyramid was build as a tomb to protect the body of an Egyptian king.  The Egyptian thought that a man’s body had to be protected and preserved so his soul could live forever.

When a king died, the people “mummified” (dried and wrapped) his body and buried it in a secret chamber deep inside an enormous pyramid, built of stone blocks to last a long time.  

It was built large to tell the world how great the king was.  Many treasures of gold and precious objects were buried with the king so that his spirit could enjoy them. Food and other necessities wee also put in the pyramid for the king in his future life.  

After the king’s mummy was placed in the pyramid, the inner passages were blocked. It took millions of stones to build a big pyramid.  Many of the blocks weighed more than a ton apiece.  A big pyramid meant the work of thousands of slaves for many years. – Dick Rogers

What causes thunder?

Thunder occurs when a flash of lightning heats the air in its path.  The heated air expands, for wing a sound wave which we hear as thunder.  What makes the loud clap of thunder that often follows a flash of lightning?  

Lightning is a big electrical spark.  During a thunderstorm, electrical charges are built up in the clouds.  If the charges become great enough, a flash of lightning occurs. As the lightning bolt jumps across the sky, it quickly heats the air in its path.  

The flash comes from a hot glowing gas in the lightning channel.  The heated air quickly expands outward as violently as if there had been an explosion.  This causes a great wave of air (or sound wave) which we hear as thunder.

Each part of the zigzag bolt causes an air wave, so you often hear, thunder as a short, sharp clap followed by a series of rumbles set up by the part of the lightning bold that is farthest away.  Thunder crackles when lightning forks out into many branches.  It takes about five seconds for the sound of thunder to travel one mile. – Dick Rogers

How Did Badminton Get Its Name?

Badminton is a game somewhat like tennis, because in both games an object is hit over a net with rackets.  But the badminton racket is lighter than a tennis racket and a feathered shuttlecock, or “bird,” is hit instead of a tennis ball.

Badminton is a present-day version of an earlier and simpler game called “battledore and shuttlecock,” which was first played several hundred years ago in India and other Eastern countries.

A group of Englishmen brought it to England. It was played so much at a place in England called Badminton that it was named after this place.

The object of the game is to bat the shuttlecock from one player to the other without allowing it to fall to the ground or bounce as a tennis ball does.

A badminton shuttlecock is often called a “bird” because it has real feathers tied to a piece of cork.The feathers guide the shuttlecock when you hit it over the net.

The “bird” often used in badminton today has a plastic crown, instead of the old feather crown. – Dick Rogers

What are stars made of?

Stars

Stars are formed from gigantic masses of hot glowing gases.  Hydrogen and helium are the most common gases in a star.  In the clearest night sky you might see a few thousand stars with unaided eye.  Every bright star is a sun, like our own sun.

Scientists tell us that a star is a huge glowing ball of hot gases.  It is a kind of gigantic atomic furnace in which the temperature at the center may be as high as several million degrees.  Hydrogen and helium are the most common gases found in a star.  Although they are made up of gases, their centers are so dense and hot that the atoms of gas are constantly colliding and fusing together into new materials.

As the atoms unite, some of their atomic energy is given off  in the form of heat and light which stream away from the star in all directions.  This is why stars shine.  Scientists can find out all this by using instruments called spectroscopes.  With these instruments they can tell from the light a star gives what the star is made of and how hot it is. – Dick Rogers

How did death valley get its name?

Death Valley

Death valley was named in 1849 but the survivors of a party of prospectors, many of whom died of heat and thirst while looking for gold in the valley.  The hottest, driest and lowest place in the United States is Death Valley.  Death Valley is a desert basin that lies mostly in Southern California.

Death Valley is about 140 miles long and 4 to 16 miles wide.  About 500 square miles of the valley are below sea level, including the lowest spot in North America (282 feet below sea lever near Bad Water).

Only about two inches of rain fall on Death Valley’s wastelands each year and the scorching heat has reached 134 degree in the shade—a record high temperature in the United States.  Despite the burning hear many kinds of plants thrive here, such as mesquite and desert holly.  You can find coyotes, rabbits, rattlesnakes, birds and many other creatures living here, too. – Dick Rogers

Why Is A Desert Dry?

Deserts cover nearly a fifth of the earth’s surface.  We would probably describe a desert as a hot, barren land where it hardly ever rains—a land so dry that few plants can grow on it, and where other

Dry Desert

forms of life also find it difficult to exits.  The desert we have just described occupies nearly a fifth of the earth’s land surface.  Large deserts can be found in all of the continents except Europe.

The driest and hottest deserts are found in the trade wind zones north and south of the Equator.  Deserts in these areas, such as the Sahara Desert of North Africa, are dry even though they may be near the ocean waters.  Here the winds blow across the desert toward the Equator and become very hot and dry, and release little of their moisture as rain.

Some deserts are dry because they are so far from the sea that the winds blowing in from the ocean lose their moisture long before they reach these deserts.  And in many cases, desert regions are cut off from the moisture laden sea air by tall mountains that catch the rainfall on their seaward side. – Dick Rogers