Science Class 7 - Winds Storms-And-Cyclones Notes

Winds, Storms and Cyclones

Welcome to the chapter on Winds, Storms and Cyclones for Class 7. In this chapter, you will learn about how wind is formed, what causes storms and cyclones, and how these natural events affect our lives. By the end of this chapter, you will understand the science behind winds, storms, and cyclones and how to stay safe during such events!

Introduction

Wind is moving air. Sometimes, wind can become very strong and cause storms or cyclones. These events can change the weather and affect people, animals, and plants.

What is Wind?

• Wind is air in motion caused by differences in temperature and pressure.
• Warm air rises and cool air rushes in to take its place, creating wind.
• Wind can be gentle (breeze) or strong (storm).

How are Storms Formed?

• Storms happen when air moves very fast and clouds gather quickly.
• Thunderstorms have lightning, thunder, and heavy rain.
• Strong winds can break trees, damage houses, and cause floods.

What are Cyclones?

• Cyclones are very strong storms with high-speed winds that move in a circle.
• They form over warm seas and can travel long distances.
• Cyclones can cause heavy rain, floods, and damage to buildings.

Effects of Winds, Storms and Cyclones

• Can destroy crops and trees.
• Can damage houses, roads, and power lines.
• Can cause floods and loss of life.
• Can change the weather quickly.

Safety During Storms and Cyclones

• Stay indoors and away from windows.
• Do not touch electrical wires or poles.
• Listen to weather reports and follow instructions.
• Store food and water for emergencies.

Fun Activity: Make a Wind Vane!

Use paper and a straw to make a simple wind vane. Place it outside and see which way the wind blows!

Summary

• Wind is moving air caused by temperature and pressure changes.
• Storms and cyclones are strong winds that can cause damage.
• It is important to stay safe during storms and cyclones.

Practice Questions

1. What causes wind?
2. What is a cyclone?
3. List two effects of storms.
4. How can you stay safe during a cyclone?
5. What is a wind vane used for?

Challenge Yourself

• Draw a cyclone and show how it moves in a circle.
• Find out about a famous cyclone in India and write two facts about it.

Did You Know?

• Cyclones are called hurricanes in America and typhoons in Asia!
• The fastest winds in a cyclone can reach over 300 km/h!

Glossary

• Wind: Moving air.
• Storm: Strong wind with rain, thunder, or lightning.
• Cyclone: A very strong storm with high-speed winds moving in a circle.
• Wind Vane: A tool to show the direction of the wind.

Answers to Practice Questions

1. Differences in temperature and pressure cause wind.
2. A cyclone is a very strong storm with high-speed winds moving in a circle.
3. Damage to houses and crops, floods, loss of life.
4. Stay indoors, listen to weather reports, avoid electrical wires.
5. To show the direction of the wind.

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Learn about winds, storms, and cyclones to stay safe and help others!