Kamis, 28 Februari 2008

Why The Sky Is Blue?

The sky usually looks blue not pink red yellow.
It gets its blue color from the sunlight thet shines through the air.
Sunlight contains all the colors of the rainbow, but these colors are scaterred as they pass through the air. Some colors are scaterred more than others, and the color you see-blue.

The sky usually looks light blue, but if you went to the top of the highest mountain, where there is less or between you and the sun to scatter the sunlight, the sky would be a deep, dark blue.

And if you rode in a rocket high above the earth, where there is no air at all to scatter the sunlight, the sky would be so dark that it would look black.
Sometimes the sky doesn't look blue. At sunrise and sunset, the light from the sun sometimes is scaterred in such away, that you see, orange, and other colors in the sky.

Minggu, 24 Februari 2008

Why a Rainbow is an Arc?



You can see a rainbow as an arc when the sun is behind you and the sky in front of you is filled with moisture. Each band of color occurs at a certain angle. The raindrops in each band lie in an arc. In the red band, for example, all the points of the arc measure about 42 degree from the line formed by the sun's rays. The other colored bends occur at angles less 42 degree from, the sun's rays.

Why Do Stars Twinkle?

Twinkle twinkle little star-why do stars twinkle?Air makes stars twinkle,
As the light from a star shines down on earth, it passes through the air around the earth. The air is always moving and changing. The changes are small, but they make the starlight bend and scatter. And thi is why a star twinkles.

The astronauts who have soared through where there is no air saw stars that didn't twinkle.

Kamis, 21 Februari 2008

why a doughnut has a hole?

The hole in doughnut can be something to eat around or stick finger in, or peek through. But you can't hold it. And once you eat the doughnut, the hole is gone.


A machine puts the hole in a doughnut. It punches the doughnut out of a flat piece of dough, the way you cut out cookies with a cooky cutter. The doughnut, hole and all, is put in boiling oil. The oil bubbles through the hole and around the doughnut until it is puffy and crisp. Without a hole, a doughnut just wouldn't be a doughnut. It would be a round, flat doughy cake with a soggy center.