Category: Physics
-
Which are the various parts of the sea?
The Bottom of the Sea The sea floor has many mountains, plains, deep valleys, and even volcanoes! Its mountain ranges are longer and wider than those on land. Its valleys are longer and deeper, too. The earth’s surface is covered with a rocky crust. The high parts are the continents and islands, and the low…
-
What are Plains?
Have you ever travelled across land where the sky seems bigger than the countryside around you? If so you probably saw a part of the earth called a plain. The land is so flat that you can see great distances all around. Most plains are lower than the land around them, but they are not…
-
What are Valleys?
If the highest part of the land is a mountaintop, what do you think the lowest place is? That’s right – a valley. Most valleys begin as land with a stream or river running through it. As the river flows along, it breaks off pieces of the land and carries them away. This deepens the…
-
What are the consequences of ground shakes?
The Ground Shakes The ground shivers, shakes, and rumbles. Whole sections of land move, and even mountains seem to move. What is happening? It’s an earthquake! What causes earthquakes? Earthquakes start in the earth’s crust. Pressure builds and pushes rocks until they bend. If you bend a stick long enough, it snaps and breaks. The…
-
How Islands were invented?
An Island is born Day after day, huge explosions filled the air. The ocean sizzled as hot rock and ash shot up from the sea floor. Soon, a large mound of dark, melted rock rose out of the water. Far out in the sea, a new volcano was born. After it rose above the surface…
-
Why do Mountains explode?
A volcano is a special kind of mountain that actually builds itself! It is made of red-hot rock that pushed up out of a crack in the earth. A volcano begins deep inside the earth when the force of hot gas pushes melted rock up. With a loud, deep rumble, the ground begins to shake…
-
Why mountains are there?
Some mountains are no more than steep hills covered with grass and trees. Others rise high into the atmosphere with snow-covered peaks. Often mountains stretch out in long chains called mountain ranges. Mountains are formed over long periods by tremendous forces in the earth. These forces move parts of the earth’s crust in different ways,…
-
Describe the plates of Earth?
The Earth’s Plates It may seem that the earth’s crust is one gigantic piece of rock. But the outer shell of the earth is divided into about 30 large and small pieces that fit together like a puzzle. These pieces are called tectonic plates. The plates move on a very hot layer of rock within…
-
Who Studies the Earth?
Some of the world’s best detectives are the people who study the earth. They are called geologists. Geologists help us learn about the earth’s resources and how to care for them. They tell us how to preserve these resources and to use them properly when we must. Some geologists study where to build homes, bridges,…
-
Are laser devices inspired by Einstein’s Theory of Stimulated Emission?
You might have come across laser pointers while attending a seminar or conference, or perhaps used it to play with your cat or dog. In the sixty years since physicists demonstrated the first laboratory prototype of a laser in 1960, it has been put to use in numerous ways from barcode readers to systems for…