Important Questions Class 7 Social Science Our Environment Chapter 4

Important Questions Class 7 Social Science Our Environment Chapter 4

Geography is the study of the planet’s physical characteristics as well as how humans have impacted certain locations, shaping both the civilisation and the planet. The fourth chapter of Class 7 Social Science, Our Environment is about Air. All around us is air. It is a combination of many gases. Approximately 78% of the air in Earth’s atmosphere contains nitrogen, while 21% is oxygen. Starting at the surface of the planet, there are five layers that make up our atmosphere. Troposphere, stratosphere, mesosphere, thermosphere, and exosphere are the five levels. Weather is the atmosphere’s state from hour to hour and day to day. The average weather best describes the climate of a location over a longer period of time. Chapter 4 Class 7 Social Science Our Environment Important Questions helps grasp the fundamentals of the chapter. Students can easily access all this and more on the Extramarks website.

It takes a lot of time to memorise important facts, places, and other things in geography. The Social Science faculty of Extramarks has designed Social Science Our Environment Class 7 Chapter 4 Important Questions using NCERT textbook, other reference books, past exam papers, and other sources. To help students comprehend each chapter, our geography experts have compiled a list of step-by-step solutions. Students can register today with Extramarks and access Class 7 Social Science Our Environment Chapter 4 Important Questions. 

Along with Important Questions Class 7 Social Science Our Environment Chapter 4, students can easily access materials like NCERT Solutions, CBSE revision notes, past year question papers, NCERT books, and more on the Extramarks website.

Important Questions Class 7 Social Science Our Environment Chapter 4- with Solutions

The Social Science experts of Extramarks have documented an entire list of Important Questions Class 7 Social Science Our Environment Chapter 4 using different sources. Air is all around us. It is a mixture of many gases. Nitrogen makes up around 78% of the air in Earth’s atmosphere, while oxygen makes up 21%. Our atmosphere comprises five layers, beginning at the planet’s surface. The five levels are the troposphere, stratosphere, mesosphere, thermosphere, and exosphere. The condition of the atmosphere from hour to hour and day to day is called the weather. The average weather for a longer period of time best captures a place’s climate. These questions and solutions help students better comprehend the chapter about Air. 

Mentioned below are a few Important Questions Class 7 Social Science Our Environment Chapter 4 and their solutions:

Question 1. What is air pressure?

Answer 1. Air pressure is defined as the pressure imposed by the weight of air on the earth’s surface. At sea level, the maximum air pressure falls as altitude increases.

Question 2. Why does it rain? What occurs when rainfall is abundant?

Answer 2. The definition of rainfall is as follows:

• Rain is defined as precipitation that falls in liquid form on the earth’s surface.
• Condensed gases that ascend above the ground owing to the strong wind pressure and descend as liquid droplets on the earth’s surface are the causes of this phenomenon.
• Gravity is what causes rain to fall on earth.
• Groundwater is mostly sourced by rainfall.
• Floods happen when there is an excess of rainfall.

Question 3. What is the atmosphere?

Answer 3. The term “atmosphere” refers to the cloud of air that envelops the planet. The bulk of the atmosphere is made up of nitrogen and oxygen, with smaller amounts of other gases, including carbon dioxide, helium, ozone, etc. The environment on earth is necessary for the existence of every living thing.

Question 4. Why does the temperature in cities differ from that in rural areas?

Answer 4. Due to the following factors, cities tend to be warmer than rural areas:

• The natural habitat of people is in villages. Cities are larger, more contemporary versions of villages with denser populations. Cities are therefore extremely populated and have higher levels of pollution. Gases released by companies and automobiles are to blame for this pollution. These gases contribute to the cities’ increasing temperatures.
• The temperature of cities is higher than that of villages because of the asphalt on roads and the concrete and metal of buildings, which absorb heat during the day and release it at night.
• Additionally, the hot and warm air is constrained by the towering structures seen in cities, raising the temperature.

Question 5. Name three types of rainfall.

Answer 5. Here are the three categories of rainfall:

• Cyclonic rainfall
• Convectional rainfall
• Orographic rainfall

Question 6. Describe the many types of atmospheric layers.

Answer 6. There are five components to the atmosphere:

• Troposphere: The first and foremost layer of the atmosphere is called the troposphere. The troposphere contains various gases in addition to the air we breathe. The troposphere rises to a typical altitude of around 13 km. This layer is where all weather-related phenomena occur.
• Stratosphere: After the troposphere is the stratosphere. The stratosphere is present up to a height of approximately 50 kilometres. The stratosphere is where aeroplanes fly since it is virtually completely free of clouds and meteorological occurrences. Additionally, this layer includes ozone gas, which shields the planet from the sun’s harmful radiation.
• Mesosphere: The mesosphere begins where the stratosphere terminates and reaches a height of 80 km. After entering the atmosphere, meteorites from space burn up here.
• Thermosphere: In this area of the atmosphere, the temperature rises more quickly as altitude rises. It helps with radio transmission since the ionosphere is present in this stratum. It stretches between 90 and 400 kilometres above sea level.
• Exosphere: The exosphere is the topmost and last layer of the atmosphere. It has air inside. Here, helium and hydrogen are typical.

Question 7. Which two gases make the bulk of the atmosphere?

Answer 7. The atmosphere is mostly composed of two gases:

• Oxygen (21 per cent)
• Nitrogen (78 per cent)

Question 8. Give a definition of wind and describe its many types.

Answer 8. The wind is the term used to describe the flow of air from high-pressure regions to low-pressure regions. There are three main categories of wind:

• Permanent winds: Wind that blows in the same direction all year long is referred to as permanent wind. Permanent winds include trade winds, easterlies, and westerlies.
• Seasonal winds: Seasonal winds are winds that alter their direction with the changing seasons. Monsoon season, for instance.
• Local Winds: Local winds are winds that are present for a brief time in a particular location. 

Question 9. Which gas creates the greenhouse effect in the atmosphere?

Answer 9. The gas responsible for the greenhouse effect in the atmosphere is carbon dioxide.

Question 10. Write a brief essay about the atmospheric pressure distribution.

Answer 10. The weight of the air exerts air pressure on the earth’s surface. This air pressure is uneven and changes at different locations. Here is an explanation of how air pressure is distributed:

• As the atmosphere rises in altitude, the atmospheric pressure rapidly decreases. The air pressure is lowest at sea level and falls as one rises in altitude.
• The temperature of the air significantly influences the pressure of the air at a specific location. The air exerts less pressure, and the hotter it is. Due to this, the air temperature rises in areas with greater temperatures. This aids in establishing a region of low pressure. Similarly, increased air pressure is felt in locations with lower temperatures.

Question 11. What is the weather like?

Answer 11. Weather refers to the atmosphere’s status from hour to hour or day to day. From day to day, the weather might fluctuate considerably. You can categorise it as hot, dry, chilly, or wet.

Question 12. Why do astronauts have to use specific clothing whenever they travel between stars?

Answer 12. There is no atmosphere or atmospheric pressure present as they fly between stars. The astronauts’ natural bodies would exert resistance in such a setting. Their blood vessels would burst, resulting in bleeding. Therefore, astronauts wear special suits whenever they participate in interplanetary travel to resist such pressure and prevent such tragic situations.

Question 13. In what ways can bacteria help plants in absorbing nitrogen from the atmosphere?

Answer 13. Nitrogen is a crucial ingredient for plants to live. However, plants are unable to absorb nitrogen from the air directly. For that reason, microorganisms are crucial in helping plants get nitrogen from the atmosphere. They ingest the atmospheric nitrogen and turn it into a useful form for plants. As a result of the bacteria’s actions, plants are provided with nitrogen in this way.

Question 14. What elements of the atmosphere are the most important?

Answer 14. The following are the primary components of the atmosphere:

• The most prevalent gas, nitrogen, makes up around 78 per cent of the atmosphere.
• The next important element is oxygen, which makes up about 21% of the atmosphere’s total air mass.
• Carbon dioxide and argon make up 0.93 and 0.03 per cent, respectively.
• In addition, trace amounts of other elements, including helium, ozone, hydrogen, and tiny dust particles, are also present.

Question 15. Why does insolation drop from the equator to the poles?

Answer 15. Because of the sun’s beams, insolation diminishes from the equator to the poles. You may define this as follows:

• Due to the equator’s relative proximity to the sun, the sun’s rays travel it across a shorter distance. These rays are vertical as well. As a result, there is more insolation at the equator.
• The rays simultaneously get increasingly angled as they travel closer to the poles. Due to the poles’ relative distance from the sun, these rays must likewise travel a greater distance to reach there. Consequently, the process generates heat.

As a result, insolation decreases as one moves from the equator to the poles.

Question 16. Using the “super cyclone” in Odisha as an example, describe the ferocity of a cyclone.

Answer 16. Cyclones from the Bay of Bengal are common in Odisha, which lies on the eastern seaboard of India.

• On October 17–18, 1999, and again on October 29, Odisha was affected by cyclones.
• The ‘depression’ that gave rise to the cyclone began in the Gulf of Thailand close to Port Blair.
• On October 25, it headed northwest before intensifying into a super cyclone and making landfall in Odisha.
• A 36-hour period of up to 260 km/hr winds was experienced.
• Trees, Kutcha homes, rooftops, industrial sheds, etc., were all uprooted or blown away.
• Communication and power cables were damaged.
• Major rivers were inundated by persistent rain. Twenty-eight coastal towns and 20 km of interior regions were destroyed, including the metropolis areas of Cuttack and Bhubaneshwar.
• Paddy crops, fruit and vegetable crops, and agricultural land rendered barren owing to salination were all damaged by 7–10 m high tidal surges.
• Thirteen million individuals were impacted. There was also a huge loss of animals.
• Mangrove forests in Paradeep and Konark, as well as teak, sal, and bamboo plantations, all perished.

Question 17. What is the connection between pressure and temperature?

Answer 17. The local temperature affects the distribution of air pressure:

• High temperatures cause the air to warm up and ascend. A low-pressure region results from this.
• Cloudy sky and rain are correlated with low pressure.
• The air is cold and heavy in low-temperature places. Therefore it sinks. A high-pressure region results from this.
• Clear, bright skies are related to high pressure.
• Air always moves from locations of high pressure to those of low pressure.

Question 18. What distinguishes the two terms, weather and climate?

Answer 18. The atmosphere’s hour-by-hour circumstances determine the weather, so while a hot, humid day could make us cranky, a breezy day or a beautiful evening might cheer us up. Over a few months, the weather might be hot or cold.

As a result, we have long-term climate projections as well as daily weather forecasts.

In the above section of Important Questions Class 7 Social Science Our Environment Chapter 4, all the significant topics of the chapter are covered.

Benefits of Solving Important Questions Class 7 Social Science Our Environment Chapter 4

This subject might be challenging for some students to remember. In an effort to assist students, Extramarks has developed Important Questions Class 7 Social Science Our Environment Chapter 4. These solutions regularly help motivate students to study. Students gather confidence by answering the important questions and going over their solutions. 

Mentioning below are some benefits of solving Important Questions Class 7 Social Science Our Environment Chapter 4:

• These solutions help students save time while preparing for the upcoming examination and cover the entire chapter.
• Students can entirely rely upon these important questions as they are made following all the guidelines laid by CBSE.
• Important Questions Class 7 Social Science Our Environment Chapter 4 covers the concepts of the entire chapter- Air.

Extramarks provides comprehensive learning solutions for students from Class 1 to Class 12. Our website has abundant resources, along with important questions and solutions. Students can easily click on the links given below to access some of these resources:

• NCERT books
• CBSE Revision Notes
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• Important formulas 
• CBSE extra questions