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Class Seven Science Chapter 8 Very short answer type
Chapter 8: Winds, Storms and Cyclones
State whether the following statement is True/False:
1. The winds coming from oceans carry water and bring rain.
2. The warm air is lighter than cold air.
3. Air moves from the region of low pressure to high pressure.
4. The equator of the earth gets less heat from the sun.
5. Lactometers are used to measure the speed of the wind.
Answers: 1. True 2. True 3. False
4. False 5. False
Match the following:
Very Short Answer Type Questions
1. What is wind?
Answer: The moving air is called wind.
2. Define the storm.
Answer: A high-speed wind is called a storm.
3. What are monsoon winds?
Answer: The movements of cold winds from the oceans towards the land are called monsoon winds.
4. What is lightning?
Answer: Lightning is a bright flash of light appears in the sky during a storm produced by thunderstorms.
5. Name the instrument used to measure the speed of the wind.
Answer: Anemometer is used to measure the speed of the wind.
6. Name the factor that increases the speed of the wind.
Answer: Reduction of air pressure increases the speed of the wind.
7. What is the speed of tornado?
Answer: A violent tornado can travel at a speed of 300 km/h.
8. Write the direction of moving air.
Answer: Air moves from the region of high pressure to the region of low pressure.
9. Define cyclone.
Answer: Cyclones are formed in warm and humid conditions that are usually found near the equator. These are also known as typhoons
10. What do you mean by a thunderstorm?
Answer: Thunderstorms are storms with heavy rains, lightning and thunder.
Short Answer Type Questions
1. Describe the formation of monsoon.
Answer: During summer, when the land gets warmed and temperature of land becomes higher than that of water in the ocean. The air above the land gets heated and rises. Therefore, the cold wind flows from the ocean towards the land. These are monsoon winds which bring water and cause rain.
2. What are the factors responsible for thunderstorms?
Answer: The basic factors used to make a thunderstorm are moisture, unstable air and lift. Moisture is used to form clouds and rain. Unstable air is relatively warm and rises upwards rapidly.
3. What happens in the winter season due to uneven heating of land and ocean water?
Answer: In the winter season, the uneven heating of land and water generates winds from the North-West colder land that carry little water. It brings a small amount of rain in the winter season.
4. What happens in the summer season due to uneven heating of land and ocean water?
Answer: In the summer season, the uneven heating of land and ocean water generates wind from the South-West direction. These winds carry a lot of water from the Indian Ocean.
5. How is the pressure difference produced in nature?
Answer: Pressure difference is produced in nature by the heat of the sun. When it falls on the earth surface, the surface of the earth gets heated and the air above it also gets warm and becomes lightweight and moves upward. Thus, the pressure difference is produced.