Category: Physics
-
How hard is the Wind Blowing?
Wind has many different names, depending on how hard it is blowing. In this question, you will find out how to tell how hard the wind is blowing by watching what it does. And you will learn some of the names we give to the different speeds of wind. In calm air, smoke rises straight…
-
How do you explain wind?
Wind When the air seems calm, and you can’t feel a wind, it doesn’t mean that the wind has stopped blowing everywhere. There are always many winds keeping the air around the earth moving. In one place, there may be a soft breeze from the north. In another place, there may be strong gusts from…
-
What makes the wind blow?
The wind moves over the land. It sways the tall grass in meadows and rustles leaves on trees. It ruffles your hair. In a storm, it whirls and roars. Wind can change a cloudy day into a sunny one by pushing clouds along. Wind is moving air. And it is the sun that makes air…
-
What is air made of?
Air doesn’t seem to be made of anything. It has no colour, taste, or smell, and you can see right through it. But air is made up of things. It is made of many kinds of gases. And these gases are made up of tiny bits called molecules. Actually, everything on the earth is made…
-
What colour is the sky?
If you could stand on the moon and look at the sky, it would always be dark black. This is because the moon has no air. If the earth had no atmosphere, our sky would stay dark, too. Instead, the sky over the earth is dark only at night when the sun doesn’t shine. Sunlight…
-
What surrounds the Earth?
Long ago, people believed the sky was a roof that stretched over the earth. Today, we know that a thick layer of air surrounds the earth like the skin on an orange. But unlike an orange skin, the air moves around the earth, and it reaches far above the earth’s surface. This moving…
-
Who studies the waters?
Many scientists study the ocean, looking into the secrets of the sea. They study how the ocean moves and how it affects the atmosphere. They study the living things in the sea and the shape of the ocean floor. Scientists who study the ocean are called oceanographers. Sometimes they work aboard ships. Some wear diving…
-
What is underground water called?
Water from Underground Not all of the earth’s water is in lakes, ponds, rivers, and oceans. A lot of it is beneath your feet – down in the ground. Rain falls. Snow melts. Much of the water seeps into the ground. It passes through holes and cracks in the soil until it reaches solid rock.…
-
Why are Lakes important?
You probably know that lakes give us food and drinking water. But did you know that lakes offer transportation and energy sources? Many lakes are important for fishing. People who live near Lake Titicaca in South America live simply by raising their own food crops and catching fish from the lake, such as trout. Other…
-
What are Lakes?
A lake is water that has land all around it. Some lakes are so big that we can’t see the other side. Lake Superior in North America is the largest freshwater lake in the world. It spreads over more than 82,100 square kilometres. Some areas of water called seas are actually lakes because land surrounds…