An Overview of Class 7 Science Winds Storms And Cyclones Worksheets
FAQs on Class 7 Science Winds Storms And Cyclones Worksheets
1. What are some expected 3-mark important questions from the CBSE Class 7 Science Chapter 8, Winds, Storms and Cyclones for the 2025-26 exam?
For the Class 7 Science exam, some frequently asked 3-mark questions from this chapter test fundamental concepts. Expect questions like:
- Explain with an example that air exerts pressure.
- Describe two ways wind currents are generated due to uneven heating on Earth.
- List three effective safety measures to take during a thunderstorm.
2. For a 5-mark question on cyclone preparedness, what advanced safety measures should a student list?
To score full marks on a 5-mark question about cyclone preparedness, students should provide a comprehensive plan as per the CBSE 2025-26 syllabus. A high-scoring answer would include:
- Before the cyclone: Heed warnings from the meteorological department, make arrangements to shift essential items and animals to safer places, and keep an emergency kit ready.
- During the cyclone: Stay indoors in a strong building, avoid touching wet switches or fallen power lines, and do not venture out.
- After the cyclone: Do not pressurise rescue forces with undue demands, cooperate with neighbours, and drink only clean, stored water.
3. Why do high-speed winds blowing over a roof sometimes cause it to fly off? Which scientific principle is crucial for answering this HOTS question?
This is a Higher Order Thinking Skills (HOTS) question. The crucial principle is that high-speed winds are accompanied by reduced air pressure. When strong winds blow over a roof, the air pressure above it decreases significantly. The air pressure inside the house remains relatively high. This pressure difference creates a powerful upward force (lift) on the roof, which can be strong enough to lift it and blow it away. Mentioning this pressure difference is key to a complete answer.
4. How are wind currents generated due to the uneven heating between the Earth's equator and the poles?
This is a very important concept. The generation of wind currents involves a few steps:
1. The region near the equator receives maximum heat from the sun, causing the air there to become warm and rise.
2. This creates a region of low pressure at the equator.
3. The air at the poles is colder and denser. This cold air sinks, creating a region of high pressure.
4. Air naturally moves from a high-pressure area to a low-pressure area. Therefore, wind blows from the poles towards the equator, creating global wind currents.
5. What is the structure of a cyclone? Explain the terms 'eye' and 'eyewall' to score full marks.
A cyclone is a large, rotating storm system with a low-pressure centre. For a high-scoring answer, describe its key parts:
- The centre of a cyclone is a calm, clear area called the eye. It has the lowest air pressure and very light winds.
- Surrounding the eye is the eyewall, a region of dense clouds, the strongest winds, and the heaviest rainfall.
- Beyond the eyewall are the spiral rainbands, which are bands of thunderstorms that curve outwards from the centre.
6. Why is it a common mistake to ignore cyclone warnings issued by the meteorological department?
Ignoring cyclone warnings is a critical mistake because modern technology allows for accurate and timely prediction. The Indian Meteorological Department (IMD) uses advanced satellites and radars to track cyclones and issue warnings 24-48 hours in advance. These warnings provide crucial time for evacuation and preparation, which can significantly reduce the loss of life and property. Believing a cyclone will change its path or won't be severe can lead to being caught unprepared in a life-threatening situation.
7. How is a tornado different from a cyclone? What key differences should be mentioned for an important exam question?
While both are violent rotating storms, there are key differences that are important for exams:
- Formation and Size: A cyclone is a massive storm system that forms over warm ocean waters and can be hundreds of kilometres wide. A tornado is a much smaller, violent funnel-shaped cloud that typically forms over land, often during severe thunderstorms.
- Duration: Cyclones can last for several days or even weeks. Tornadoes are usually short-lived, lasting from a few minutes to an hour.
- Wind Speed: The wind speeds in a violent tornado (up to 300 km/h or more) can be much higher than in a typical cyclone.
8. How does the principle 'air exerts pressure' explain why it is difficult to ride a bicycle against the direction of the wind?
This is an excellent application-based question. When you ride a bicycle, you are moving through the air. The principle that air exerts pressure means the air pushes against all surfaces, including your body and the bicycle. When you ride against the wind, you are moving into a stream of air that is already moving towards you. This moving air exerts a significant amount of pressure or force, known as air resistance or drag. You must work much harder to overcome this opposing force, which is why it feels difficult.
