RBSE Solutions Class 11 Physical Geography Chapter 13 Air Pressure Belts and Winds

RBSE Class 11 Physical Geography Chapter 13 Multiple Choice Questions

 

Question 1. Who discovered air pressure?
(a) Trivartha
(b) Ferrel
(c) Gurich
(d) Finch
Answer: (c) Gurich
In simple words: A person named Gurich was the first to find out about air pressure. Air pressure is the force that air pushes down with.

🎯 Exam Tip: Remember key scientists and their discoveries, as these often appear in multiple-choice questions.

 

Question 3. Which is the hot and dry wind that runs in the plains of northern India and Pakistan?
(a) Chinook
(b) Loo
(c) Mistral
(d) Bora
Answer: (b) Loo
In simple words: The Loo is a very hot and dry wind that blows in northern India and Pakistan, especially during summer afternoons. It makes the weather very uncomfortable.

🎯 Exam Tip: Local winds are often specific to regions and have unique characteristics like temperature and humidity.

 

Question 4. Winds that run in the fixed direction throughout the year are called:
(a) Uncertain winds
(b) Seasonal Winds
(c) Permanent winds
(d) Local Winds
Answer: (c) Permanent winds
In simple words: Winds that always blow in the same direction all year long are known as permanent winds. These winds are very reliable.

🎯 Exam Tip: Distinguish between permanent (global), seasonal (monsoon), and local winds based on their duration and direction patterns.

 

Question 5. The 'Doldrum' belt is found:
(a) near the Equator
(b) near the Tropic of Cancer
(c) near the Tropic of Capricorn
(d) near the Arctic Circle
Answer: (a) near the Equator
In simple words: The Doldrum belt is a calm area with very little wind, located close to the Equator. This is due to rising warm air.

🎯 Exam Tip: Remember the Doldrums are also called the Intertropical Convergence Zone (ITCZ) and are known for calm winds and frequent rainfall.

RBSE Class 11 Physical Geography Chapter 13 Very Short Answer Type Questions

 

Question 1. What is the standard unit of measuring air pressure?
Answer: The standard unit for measuring air pressure is Millibar. This unit helps scientists compare how much air is pressing down at different places.
In simple words: Millibar is the usual way to measure how strong the air pressure is.

🎯 Exam Tip: Always specify units when asked for measurements to ensure full marks.

 

Question 3. Which is the wind that blows in the Alps Hill region?
Answer: The wind that blows in the Alps mountainous region is called Fohn. This wind comes from the southern side of the Alps and moves down towards the north along the slopes, bringing warm, dry air.
In simple words: The Fohn wind blows in the Alps, moving down from the mountainsides.

🎯 Exam Tip: Recognize specific local winds by their regional names and characteristics.

 

Question 4. What is the expanse of the equatorial low - pressure belt?
Answer: The equatorial low-pressure belt stretches between 5° north and 5° south latitudes. It is located on both sides of the equator, where warm air rises, leading to low pressure.
In simple words: The equatorial low-pressure belt is a narrow band around the equator, from 5° North to 5° South.

🎯 Exam Tip: Clearly state the latitude ranges when describing pressure belts.

 

Question 5. What is wind?
Answer: Wind is the natural, noticeable movement of air. It is essentially the movement of air across the Earth's surface in any direction and at various speeds. This movement happens because of differences in air pressure.
In simple words: Wind is simply moving air that we can feel.

🎯 Exam Tip: Define geographical terms precisely, including the cause and nature of the phenomenon.

RBSE Class 11 Physical Geography Chapter 13 Short Answer Type Questions

 

Question 1. What is air pressure?
Answer: Our Earth is surrounded by an atmosphere, which is a thick layer of many gases thousands of kilometers high. This gaseous layer pushes down on the land, creating what we call air pressure. It is often measured as the atmospheric pressure on a specific area of the surface. For example, the average air pressure on the ocean surface is about 1013.25 millibars. Air pressure generally gets lower as you go higher above the surface. At an altitude of around 540 meters from sea level, the air pressure is half of what it is at sea level.
In simple words: Air pressure is the force that the weight of the air above us pushes down on the Earth's surface. It gets lighter as you go higher up.

🎯 Exam Tip: When defining air pressure, mention its cause (weight of atmosphere), how it's measured (millibars), and its general behavior with altitude.

 

Question 2. What is Doldrum?
Answer: The Doldrum is a belt of low pressure located around the equator, extending from the equator to about 5° latitude in both the northern and southern hemispheres. In this belt, temperatures are high all year, causing air to rise and creating low air pressure. Surface winds are generally calm here. This area is also known as the equatorial 'belt of calm' or the 'Doldrum Belt' due to the upward movement of air.
In simple words: Doldrums are calm areas near the equator where warm air rises, causing low pressure and very little wind.

🎯 Exam Tip: Describe the location (latitudes), key characteristic (low pressure, calm winds), and the reason (high temperature, rising air) for the Doldrums.

 

Question 3. What is meant by prevailing winds?
Answer: Prevailing winds are permanent winds that blow in a consistent direction and fixed order throughout the year, driven by Earth's air pressure system. These winds include trade winds, westerly winds, and polar winds. Because they blow consistently in a particular sequence all year, they are also known as permanent winds, planetary winds, or global winds. They play a crucial role in global heat distribution.
In simple words: Prevailing winds are global winds that blow steadily in the same direction all year long, like trade winds or westerlies.

🎯 Exam Tip: Mention the consistent direction and year-round nature of prevailing winds, along with their alternative names, to provide a complete definition.

 

Question 4. What is meant by 'Loo'?
Answer: 'Loo' refers to extremely hot and dry winds that blow during summer afternoons, mainly in the north-western parts of India and the plains of Pakistan. These winds usually come from the west between May and June. The Loo makes the weather very hot and uncomfortable, often causing crops and grasses to dry up due to its intense heat and lack of moisture.
In simple words: Loo is a very hot, dry summer wind that blows in parts of India and Pakistan, making the weather unbearable.

🎯 Exam Tip: When defining local winds, include their region, season, characteristics (hot/cold, dry/moist), and impact.

 

Question 5. Write the names of factors affecting air pressure.
Answer: The main factors that influence air pressure are temperature, altitude (height), water vapor, and various dynamic factors. Here is a brief explanation of each:
1. Temperature: Air pressure and temperature often have an inverse relationship. Areas with higher temperatures tend to have lower air pressure, while areas with lower temperatures generally have higher air pressure.
2. Water vapor: The more water vapor present in the air, the lower the air pressure. Conversely, air that is dry typically has higher air pressure.
3. Height: Air pressure decreases as altitude increases from sea level because there is less air above to press down.
4. Dynamic reason: Dynamic factors like the Earth's rotation and convergence/divergence of air masses also play a significant role in determining global air pressure patterns.
In simple words: Air pressure changes because of how hot it is, how high you are, how much water is in the air, and how the Earth spins.

🎯 Exam Tip: Clearly list and briefly explain each factor affecting air pressure, showing an understanding of their relationship.

Air pressure belts:

 

Thermal Air Pressure Belt and Dynamic Air Pressure Belt Overview
Answer: Air pressure belts around the world are shaped by the Earth's rotating motion and the relationship between temperature and pressure. Based on these, there are two main types of air pressure belts: thermally induced belts and dynamically induced belts.
The major air pressure belts found globally are:
- **Thermal Air Pressure Belts:**
- Equatorial Low Pressure Belt
- Polar High Pressure Belt
- **Dynamic Air Pressure Belts:**
- Subtropical High Pressure Belt
- Subpolar Low Pressure Belt
These belts help distribute heat and moisture around the Earth, influencing global climate patterns.
In simple words: Global air pressure belts are formed by heat and Earth's spin, creating areas of high and low pressure, like the equatorial low and polar high belts.

🎯 Exam Tip: When classifying air pressure belts, always differentiate between thermally induced and dynamically induced belts and name the specific belts under each category.

 

1. Equatorial low pressure belt:
Answer: This belt stretches from 5° North to 5° South latitude on both sides of the equator. Because the sun's rays hit this area directly all year, the temperature is always high, resulting in low air pressure. The atmosphere here has a lot of water vapor, making the air less dense. The Earth's rotation speed is highest at the equator, which creates the strongest centrifugal force here. In this belt, horizontal surface winds are not common; instead, the high temperatures cause the air to lighten and rise upwards, leading to convection currents. This belt is also known as the equatorial 'belt of calm' or the 'Doldrum Belt'. This is a thermally formed belt, important for global weather.
In simple words: The Equatorial low pressure belt is near the equator, with high temperatures, lots of moisture, and rising air, leading to calm conditions and low pressure.

🎯 Exam Tip: Focus on the direct relationship between high temperature, rising air, and low pressure when describing the equatorial low pressure belt.

 

2. Sub - tropical High Pressure Belt:
Answer: These belts are found between 30° to 35° latitude in both hemispheres, north and south of the equator. They are characterized by high temperatures, high air pressure, and clear skies throughout the year. A notable feature of this belt is the presence of hot deserts on the western edges of continents within this region. These belts are dynamically formed due to descending air.
In simple words: The Sub-tropical High Pressure Belt is found around 30°-35° latitude, known for high pressure, clear skies, and many hot deserts.

🎯 Exam Tip: Connect the subtropical high-pressure belts with descending air, high pressure, clear skies, and the location of major deserts.

 

3. Subpolar Low Pressure Belt:
Answer: This belt is located between 60° to 65° north and south latitudes. Although these latitudes experience low temperatures, lower air pressure is found here instead of high pressure. The main reason for this is the Earth's rotational speed, which causes air to diverge from these regions. Additionally, warm ocean currents in these areas lead to higher temperatures, which further contributes to lower air pressure. This is a dynamically induced belt, crucial for storm formation.
In simple words: The Subpolar Low Pressure Belt, found around 60°-65° latitude, has low air pressure despite cold temperatures, mainly due to Earth's rotation.

🎯 Exam Tip: Highlight that subpolar low pressure is dynamically induced (due to Earth's rotation) rather than thermally induced.

 

4. Polar high pressure belt:
Answer: Near the poles, temperatures are very low, leading to consistently high air pressure. These belts, located in both hemispheres, are created by intense cold. The polar regions and their surrounding areas remain covered in ice throughout the year, so the air near the surface is very cold and heavy. This heavy, cold air sinks, causing high pressure. This makes it difficult to get detailed surface pressure data from these extreme regions. These are thermally induced belts due to extreme cold.
In simple words: The Polar high pressure belt is near the Earth's poles, where very cold, heavy air sinks, causing high air pressure all year.

🎯 Exam Tip: Explain that polar high pressure is thermally induced by the extremely low temperatures at the poles.

 

Question 2. What is meant by wind? How many types of winds are there? Describe.
Answer: Wind is the noticeable natural movement of air, which flows from areas of high air pressure to areas of low air pressure. This movement is a natural attempt to balance differences in air pressure. If the Earth were still and flat, winds would blow directly from high to low-pressure areas at right angles to isobars (lines of equal pressure). However, in reality, this doesn't happen because several factors influence wind direction and speed. Winds are generally classified into three main types:
**Types of Winds:**
1. Permanent Winds (e.g., Trade Winds, Westerlies, Polar Winds)
2. Periodic Winds (e.g., Monsoon Winds, Land Breeze, Sea Breeze, Mountain Breeze, Valley Breeze)
3. Local Winds (e.g., Chinook, Fohn, Bora, Sirocco, Harmattan, Mistral, Blizzard, Loo)
Each type has distinct patterns and causes, affecting regional climates.
In simple words: Wind is moving air from high to low pressure. There are three main kinds: permanent (always blow), periodic (change with seasons), and local (affect small areas).

🎯 Exam Tip: Start with a clear definition of wind, then list and briefly categorize its types, distinguishing them by duration and scale.

 

1. Permanent Winds:
Answer: Permanent winds are those that blow consistently in a fixed direction and order throughout the entire year. These winds are also known by other names such as prevailing winds, planetary winds, global winds, or traditional winds. They are closely linked to the Earth's main air pressure belts. The most important permanent winds include Trade winds, Westerlies, and Polar Winds. These winds help distribute heat globally.
In simple words: Permanent winds blow in the same direction all year long, like trade winds or polar winds, and are also called global winds.

🎯 Exam Tip: When describing permanent winds, emphasize their consistent direction and duration, and name the major types.

 

2. Periodic Wind:
Answer: Periodic winds are those that change their direction based on the weather or time of day/year. These winds are not constant like permanent winds. Examples of periodic winds include:
* Monsoon Winds
* Land Breeze and Sea Breeze
* Mountain and Valley Breeze
These winds are crucial for regional weather patterns, especially for rainfall.
In simple words: Periodic winds change direction with the seasons or time of day, like monsoons or sea breezes.

🎯 Exam Tip: Define periodic winds by their changing nature and provide examples that clearly illustrate this characteristic.

 

3. Local Winds:
Answer: Local winds are those that blow due to differences in temperature and air pressure in a specific small area. These winds are different from the larger prevailing winds. They can be hot, cold, ice-filled, or dust-rich, depending on the local conditions. Local winds can have both good and bad effects on the areas they blow through. Some major local winds include Chinook, Fohn, Bora, Sirocco, Harmattan, Khamsin, Mistral, Blizzard, Brick Fielder, and Willy-Willy. Their impact is highly localized.
In simple words: Local winds are small-area winds caused by local temperature differences, and they can be hot, cold, or dusty.

🎯 Exam Tip: Mention that local winds are caused by localized pressure differences and give examples that show their diverse characteristics and effects.

 

Question 3. Perform a scientific analysis of the principles related to the origin of monsoon winds.
Answer: The word 'monsoon' comes from the Arabic word 'Mausim,' meaning weather. Monsoon winds are winds that change direction with the weather. Several concepts explain their origin:
**1. Thermal Concept:** This theory suggests that monsoons originate from the uneven heating and cooling of land and water (terrestrial and aquatic parts of Earth). In summer, land heats up more, creating low pressure, so winds move from the cooler sea towards the land. This is the Summer Monsoon. In winter, land cools more, creating high pressure, and winds blow from land to oceans, forming the Winter Monsoon (also called the north-eastern monsoon). This heating difference drives the system.
**2. Motion Concept (Dynamic Concept):** Flon emphasized the dynamic origin of monsoons, focusing on air pressure and the shifting of air belts, rather than just thermal differences. Monsoon winds occur due to the meeting of trade winds near the equator, forming the tropical convergence zone (ITC). Its northern boundary is the NITC and the southern boundary is the SITC. This ITC contains a belt of Doldrums, where equatorial Westerlies winds blow.
During the Summer solstice, the NITC moves north, reaching up to 30° North Latitude, covering South East Asia. This movement establishes the Doldrum's equatorial westerly winds in these areas. Similarly, when the sun moves south during the Winter solstice, the system shifts south.
**3. Modern Concept (Jet Stream Concept):** This concept identifies the 'jet stream' as crucial. In southern Asia, a sub-tropical westerly jet stream flows rapidly from west to east in the troposphere at about 12 km altitude. Its height is lower at the poles. In the northern hemisphere during winter, the Himalayas and Tibet Plateau split this jet stream. Its northern branch flows north of the Tibetan Plateau, and its main branch flows south of the Tibetan Plateau and Himalayas, following a cyclonic path over Afghanistan and Pakistan, leading to autumnal monsoons. In summer, after March 21, as the sun moves north, the polar surface high air pressure weakens, and the high-level westerly jet stream shifts northward. This high-level low pressure then extends into north-western India and Pakistan. This existing low pressure on land, combined with the high-level low pressure pulling winds upwards, causes a sudden burst of the south-west monsoon. This shift is key to monsoon timing.
In simple words: Monsoons are winds that change direction with seasons. They are explained by how land and sea heat up differently (thermal), how air pressure belts move (dynamic), and the role of high-altitude jet streams (modern).

🎯 Exam Tip: For complex concepts like monsoon origin, clearly separate and explain each theory (Thermal, Dynamic, Modern) and highlight their key mechanisms and contributing factors.

RBSE Class 11 Physical Geography Chapter 13 Multiple Choice Questions

 

Question 1. Maximum air pressure is found:
(a) Near the earth's surface
(b) In the stratosphere
(c) In the upper part of the earth
(d) None of the options
Answer: (a) Near the earth's surface
In simple words: Air pressure is highest closest to the ground because there is more air above it pushing down.

🎯 Exam Tip: Remember that air density and pressure are highest at lower altitudes due to the weight of the air column above.

 

Question 2. Where does the rotation velocity of the earth get increased?
(a) On the Tropic of cancer
(b) On the Equator
(c) On the Tropic of Capricorn
(d) On the Poles
Answer: (b) On the Equator
In simple words: The Earth spins fastest at the Equator because it is the widest part.

🎯 Exam Tip: Relate the Earth's rotational speed to its circumference at different latitudes; the equator has the largest circumference and thus the fastest linear speed.

 

Question 3. Which months have been selected mainly for distribution of air pressure?
(a) February and April
(b) March and August
(c) May and September
(d)
Answer: [Not provided in source]
In simple words: [Explanation not provided in source]

🎯 Exam Tip: In geography, January and July are often used to study air pressure distribution as they represent extreme seasonal conditions.

 

Question 4. The winds coming from the west are called:
(a) Trade winds
(b) Westerlies
(c) Polar winds
(d) Monsoon winds
Answer: (b) Westerlies
In simple words: Winds that mostly blow from the west are known as Westerlies.

🎯 Exam Tip: Learn the general direction of global wind belts (Trade winds from east, Westerlies from west, Polar winds from east) to easily identify them.

 

Question 5. The area of transmission of the Roaring Forties is:
(a) Between 40° - 50° latitude in the Southern Hemisphere
(b) Near 50° latitude in the Southern Hemisphere
(c) Near 60° latitude in the Southern Hemisphere
(d) Near 50° latitude in the Northern Hemisphere
Answer: (a) Between 40° - 50° latitude in the Southern Hemisphere
In simple words: The Roaring Forties are strong westerly winds found in the Southern Hemisphere between 40° and 50° latitude.

🎯 Exam Tip: Remember the specific latitude bands for the "Roaring Forties," "Furious Fifties," and "Shrieking Sixties" in the Southern Hemisphere.

 

Question 6. The cold winds in Siberia are called:
(a) Bora
(b) Mistral
(c) Bur an
(d) Jonda
Answer: (c) Bur an
In simple words: The very cold winds that blow in Siberia are known as Buran.

🎯 Exam Tip: Local winds often have unique names in different regions; learn the common ones and their locations.

 

Question 1. Match column A with column B in the following:

Answer:
1. (d) Equatorial low pressure belt: Between 5° North to 5° South latitudes
2. (c) Sub - tropical high pressure belt: Between 30° - 35° latitudes in both hemispheres
3. (a) Sub - polar low pressure belt: Between 60° - 65° latitudes in both hemispheres
4. (b) Polar high pressure belt: Near the poles in both hemispheres
In simple words: Match each air pressure belt with its correct location around the Earth based on latitude.

🎯 Exam Tip: Memorize the approximate latitude ranges for each major air pressure belt to correctly match them.

 

Question 2. Match column A with column B in the following:

Answer: [Not provided in source]
In simple words: [Explanation not provided in source]

🎯 Exam Tip: Knowing the regional names and typical locations of local winds is essential for matching questions. For example, Chinook is known for the Rocky Mountains, Sirocco for the Mediterranean from the Sahara, and Harmattan for West Africa.

RBSE Class 11 Physical Geography Chapter 13 Very Short Answer Type Questions

 

Question 1. Why does air pressure decrease?
Answer: Air pressure decreases because the atmosphere's pressure is not consistent everywhere and changes with atmospheric conditions. When air gets more heat, it expands and becomes less dense, which then reduces the air pressure. This is a fundamental principle of atmospheric science.
In simple words: Air pressure drops because hot air expands and becomes lighter, pushing down less.

🎯 Exam Tip: Link decreasing air pressure to factors like increasing temperature and altitude, which cause air to become less dense.

 

Question 2. Which weather phenomena are controlled by air pressure?
Answer: Many weather phenomena are directly controlled by air pressure. These include elements like clouds, rain, storms, dust storms, and wind itself. Changes in air pressure drive many atmospheric processes.
In simple words: Air pressure controls weather events like clouds, rain, storms, and wind.

🎯 Exam Tip: Understand that differences in air pressure are the primary cause of wind and thus influence most weather patterns.

 

Question 3. How is rain possible?
Answer: Rain is possible because winds carry humidity from the oceans to the continents. As this moisture-laden air cools and rises, it condenses to form clouds, eventually leading to precipitation. This global transport of water vapor is essential for rainfall on land.
In simple words: Winds carry moisture from oceans to land, which forms clouds and then falls as rain.

🎯 Exam Tip: Focus on the role of winds in transporting moisture from oceans to land, which is a key step in the water cycle leading to rainfall.

 

Question 4. Why is there a difference in air pressure?
Answer: Differences in air pressure across the globe exist due to variations in controlling factors such as temperature, altitude, and the amount of water vapor in the air. These factors are not uniform, leading to an uneven distribution of atmospheric pressure. For instance, warmer areas typically have lower pressure.
In simple words: Air pressure is different in places because of changes in temperature, height, and how much water vapor is in the air.

🎯 Exam Tip: Emphasize that non-uniform distribution of heat, height, and moisture content are the main reasons for air pressure variations.

 

Question 5. What is the sub - tropical high pressure belt mainly known for?
Answer: The sub-tropical high-pressure belt is primarily known for housing most of the world's hot deserts. These deserts are typically located on the western edges of continents within this belt, due to the stable, descending air and lack of moisture.
In simple words: The sub-tropical high-pressure belt is famous for having many hot deserts.

🎯 Exam Tip: Connect the subtropical high-pressure belts directly with the occurrence of major hot deserts due to dry, descending air.

 

Question 6. What does horse latitude mean?
Answer: Horse latitudes refer to the areas of sub-tropical high-pressure belts found on both sides of the equator, between 30° - 35° latitudes. These regions are characterized by calm winds and clear skies. Historically, sailing ships carrying horses would often get stuck here, leading to the name as horses were sometimes thrown overboard to save water.
In simple words: Horse latitudes are calm, high-pressure areas around 30°-35° north and south of the equator.

🎯 Exam Tip: Define horse latitudes by their location (30°-35°), association with high pressure, and calm conditions, noting the historical context of the name.

 

Question 7. In the sub - polar belt, the temperature decreases, but the air pressure is low. Why?
Answer: In the sub-polar low-pressure belt, low temperatures are common. However, despite the cold, the air pressure remains low, not high. The main reason for this phenomenon is the Earth's rotational speed. This rotation creates a dynamic effect that causes air to diverge and rise in these latitudes (60°-65°), leading to lower air pressure even with cold temperatures. This rising air contributes to storm formation.
In simple words: Even though the sub-polar belt is cold, its air pressure is low because the Earth's spin makes air rise and spread out there.

🎯 Exam Tip: Distinguish between thermally and dynamically induced pressure belts; sub-polar low pressure is dynamic, influenced more by Earth's rotation than by temperature alone.

 

Question 8. What is meant by isobars?
Answer: Isobars are lines on a map that connect areas with the same air pressure, whether on land or sea. They are used to show the distribution of air pressure. When isobars are close together, it means there is a big change in pressure over a short distance, which usually causes strong winds.
In simple words: Isobars are lines on a map that connect all places having the exact same air pressure.

🎯 Exam Tip: Emphasize that isobars connect points of equal pressure and their spacing indicates the pressure gradient (wind speed).

 

Question 9. Why is there a seasonal change in air pressure belts?
Answer: Air pressure belts do not stay in the same position all year; they shift seasonally. This happens due to the apparent movement of the sun towards the north and south, which changes where sunlight hits the Earth most directly. Additionally, the differing ways land and water heat up and cool down also contribute to these seasonal shifts in air pressure patterns. This influences global weather patterns significantly.
In simple words: Air pressure belts move with the seasons because the sun's position changes, and land and water heat up differently.

🎯 Exam Tip: Explain that the seasonal shift of pressure belts is mainly due to the sun's apparent movement and the differential heating of land and sea.

 

Question 12. Why is the rate of decrease of air pressure not equal?
Answer: The rate at which air pressure drops is not always the same. This is because several factors like the density of the air, the temperature, the amount of water vapor in the atmosphere, and Earth's gravitational force all vary. These changes make the air pressure decrease at different rates in different places. The density of air changes with altitude, meaning fewer air molecules are higher up, which directly affects pressure.
In simple words: Air pressure doesn't drop evenly as you go higher because things like air density, temperature, and water vapor are different everywhere.

🎯 Exam Tip: Remember that air pressure is affected by both atmospheric composition and external forces like gravity, leading to its non-uniform decrease.

 

Question 13. Why do humans use oxygen cylinders and special suits while climbing high mountain peaks?
Answer: When climbing high mountain peaks, the air becomes very thin and light. This causes the air pressure to drop a lot. To stay safe and healthy, climbers need to use oxygen cylinders to breathe easily and special suits to balance the low outside air pressure with their body's internal pressure. This helps them get enough oxygen, as the air gets thinner at higher altitudes.
In simple words: People use oxygen and special suits on high mountains because the air is thin and pressure is low, which makes it hard to breathe and stay balanced.

🎯 Exam Tip: Highlight both reasons: overcoming oxygen scarcity and balancing body pressure to avoid adverse health effects.

 

Question 14. Where do the winds move from?
Answer: Winds always move from areas where the air pressure is high towards areas where the air pressure is low. This movement happens naturally as the atmosphere tries to balance itself, similar to how water flows downhill. Air always seeks to move from a place of more particles to a place of fewer particles.
In simple words: Winds move from places with high air pressure to places with low air pressure.

🎯 Exam Tip: The key concept here is that winds are driven by pressure gradients, always moving from high to low pressure zones.

 

Question 15. What does Pressure/Barometric gradient mean?
Answer: The pressure gradient, also called the barometric slope, is the difference in air pressure between any two locations. It's a measure of how quickly air pressure changes over a certain distance. A larger difference in pressure over a shorter distance means a stronger pressure gradient. The steeper the gradient, the stronger the winds will be.
In simple words: Pressure gradient means how much air pressure changes between two spots.

🎯 Exam Tip: Understand that the pressure gradient's strength directly affects wind speed; a steeper gradient means stronger winds.

 

Question 16. What is the Coriolis effect?
Answer: The Coriolis effect is the deflecting force that causes winds to curve as they move across the Earth. This effect happens because the Earth spins on its axis. Instead of blowing in a straight line, winds are turned to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This is an important factor in understanding global wind patterns.
In simple words: The Coriolis effect is when Earth's spin makes winds curve, turning them right in the north and left in the south.

🎯 Exam Tip: Remember that the Coriolis effect is a result of Earth's rotation and is responsible for the deflection of winds and ocean currents.

 

Question 17. On what two bases are winds mainly divided on the basis of their area of influence and duration?
Answer: Winds are mainly divided into three types based on their area of influence and how long they last: Permanent Winds, Periodic Winds, and Local Winds. These categories help us understand the different patterns and causes of air movement around the world. These divisions are fundamental to understanding global climate systems.
In simple words: Winds are divided into three main kinds: Permanent, Periodic, and Local winds, based on how much area they cover and how long they blow.

🎯 Exam Tip: Be ready to name and briefly describe each of the three main types of winds: permanent, periodic, and local.

 

Question 18. What are trade winds?
Answer: Trade winds are permanent winds that blow in both the Northern and Southern Hemispheres. They move from the sub-tropical high-pressure belts towards the equatorial low-pressure belts. These winds were historically important for sailing ships that traveled across oceans for trade. These consistent winds made long sea voyages more predictable.
In simple words: Trade winds are constant winds that blow from sub-tropical areas towards the equator in both parts of the world.

🎯 Exam Tip: Note the direction of trade winds (high to low pressure, towards the equator) and their historical significance for navigation.

 

Question 19. What do you mean by the westerlies winds?
Answer: Westerlies winds are also permanent winds found in both hemispheres. They blow from the sub-tropical high-pressure belts towards the sub-polar low-pressure belts. Unlike trade winds, westerlies blow from west to east, influencing weather patterns in the middle latitudes. They are a crucial component of global atmospheric circulation.
In simple words: Westerlies are constant winds that blow from sub-tropical high-pressure zones to sub-polar low-pressure zones.

🎯 Exam Tip: Distinguish westerlies from trade winds by their direction (west to east) and the pressure belts they connect (sub-tropical high to sub-polar low).

 

Question 20. What is meant by monsoon winds?
Answer: The word "monsoon" comes from the Arabic word 'Mausim', which means "weather" or "season." Monsoon winds are those winds that change their direction with the seasons. These seasonal changes in wind direction bring distinct wet and dry periods to many parts of the world, especially in South Asia. Monsoons are crucial for agriculture in affected regions.
In simple words: Monsoon winds are seasonal winds that change direction, bringing different weather patterns like wet and dry seasons.

🎯 Exam Tip: Focus on the key characteristic of monsoon winds: their seasonal reversal of direction and the associated wet/dry periods.

 

Question 21. What are local winds?
Answer: Local winds are air movements that occur due to differences in temperature and air pressure over a specific small area. These winds are influenced by the local geography and are often named after the region where they occur. They typically have a smaller scale and duration compared to global wind systems. For example, a sea breeze is a type of local wind.
In simple words: Local winds are small-scale winds caused by temperature and pressure differences in a certain area.

🎯 Exam Tip: Emphasize that local winds are tied to specific geographical features and have limited reach, contrasting them with planetary winds.

 

Question 22. Write the names of some major local winds.
Answer: Some of the major local winds found around the world include: Chinook, Blizzard, Bora, Fohn, Harmattan, Karaburan, Loo, Gibli, Pamparo, Jonda, Brick Fielder, Khamsin, Sirocco, and Willy - Willy. Each of these winds has distinct characteristics and impacts on its local environment. These names represent a variety of unique weather phenomena.
In simple words: Some big local winds are Chinook, Blizzard, Bora, Fohn, Harmattan, Loo, and Sirocco.

🎯 Exam Tip: While listing, try to recall at least 5-7 major local winds from different regions to show broad knowledge.

 

Question 23. What is Harmattan?
Answer: Harmattan is a warm and dry wind that blows in the eastern part of the Sahara Desert in Africa. It travels from the north-east to the east towards the west. This wind is known for its dryness and can bring dust, but it also makes the hot, humid weather on the West African coast more pleasant. It's often called "Doctor Air" because of its refreshing effect.
In simple words: Harmattan is a warm, dry wind that blows from the Sahara Desert in Africa, making humid areas feel drier and more pleasant.

🎯 Exam Tip: Remember Harmattan's origin (Sahara Desert), its dry nature, and its nickname "Doctor Air" due to its drying effect on humid coastal areas.

RBSE Class 11 Physical Geography Chapter 13 Short Answer Type Questions (SA-1)

 

Question 1. What is the relation between air pressure and wind circulation?
Answer: Air pressure and wind circulation are closely linked. The main reason winds blow is due to differences in air pressure. Air always moves from areas of high pressure to areas of low pressure. This movement also affects rainfall and temperature, as winds carry heat from warmer to cooler regions and bring moisture from oceans to land, causing rain. Winds help distribute heat around the globe, maintaining Earth's energy balance.
In simple words: Air pressure differences cause winds to blow, which then affect rain and temperature by moving heat and moisture.

🎯 Exam Tip: Explain that air pressure differences create a pressure gradient, which is the driving force behind wind, directly influencing weather and climate.

 

Question 2. Describe the characteristics of the Equatorial low pressure belt.
Answer: The Equatorial low pressure belt has several key characteristics:
1. It is located on both sides of the equator, usually between 5° North and 5° South latitudes.
2. Temperatures are always high here because the sun's rays hit this area directly all year round. This high temperature causes the air pressure to be low.
3. The atmosphere in this belt has a lot of water vapor.
4. Horizontal winds do not blow much here; instead, vertical air movements (convectional currents) are common, causing air to rise. This leads to calm conditions.
5. It is also known as the "belt of calm" or the "Doldrum belt" due to the lack of horizontal winds and generally settled weather. This region is a thermally induced pressure belt, driven by solar heating.
In simple words: The Equatorial low pressure belt is near the equator, always hot with low air pressure, lots of moisture, and mostly calm air with air rising upwards. It's called the Doldrums.

🎯 Exam Tip: Focus on the high temperature, low pressure, high humidity, vertical air currents, and the "Doldrums" nickname as essential points.

 

Question 3. What is the situation of air pressure in January?
Answer: In January, the sun shines almost directly over the Tropic of Capricorn, which is in the Southern Hemisphere. This means the Southern Hemisphere experiences high temperatures and, as a result, low air pressure. Areas of low air pressure develop over the interior parts of continents like South America, South Africa, and Australia. Meanwhile, fully developed sub-tropical high-air pressure regions are found over the continents in the Northern Hemisphere. This seasonal shift is a fundamental aspect of global atmospheric circulation.
In simple words: In January, the sun is over the Southern Hemisphere, making it warm with low pressure, while the Northern Hemisphere has cooler temperatures and high pressure.

🎯 Exam Tip: Connect the sun's position (Tropic of Capricorn) directly to temperature and resulting pressure patterns in both hemispheres during January.

 

Question 5. How have the trade winds been named? Explain.
Answer: Trade winds got their name because of their historical importance in facilitating trade. In ancient times, sailing ships relied on these consistent winds to travel across the oceans for commerce. These reliable winds, blowing steadily in a fixed direction, made sea voyages predictable and efficient for merchants. They are also known as north-eastern trade winds in the Northern Hemisphere and south-eastern trade winds in the Southern Hemisphere.
In simple words: Trade winds are named this way because old sailing ships used them a lot for trading goods across the sea.

🎯 Exam Tip: Explain the direct link between "trade" and "trade winds," emphasizing their role in early global commerce and navigation.

 

Question 6. Describe the characteristics of trade winds.
Answer: Trade winds have several distinct characteristics:
1. They are generally dry and calm because they descend near the sub-tropical high-air pressure regions.
2. As they travel over water bodies, they absorb moisture, picking up water vapor along their path.
3. By the time they reach the equator, these winds are nearly full of water vapor (saturated). This makes them prone to releasing moisture.
4. Near the equator, trade winds from both the Northern and Southern Hemispheres meet and rise upwards, leading to heavy rainfall in the equatorial region. This convergence helps drive the Hadley cell circulation.
In simple words: Trade winds start dry and calm, pick up moisture over oceans, become full of water near the equator, and then cause a lot of rain when they meet.

🎯 Exam Tip: List their origin (dry), moisture absorption, saturation at the equator, and role in equatorial rainfall as key characteristics.

 

Question 7. Describe the features of polar winds.
Answer: Polar winds have the following features:
1. These winds move from the very cold polar regions towards the sub-polar regions.
2. In the Northern Hemisphere, they blow from the north-east to the south-west. In the Southern Hemisphere, their direction is from the south-east to the north-west.
3. They are extremely cold and dry because they originate from the frigid polar areas.
4. Due to their very low temperature, their ability to hold or absorb water vapor is also very low. These winds are a critical part of the Earth's heat transport system, moving cold air to lower latitudes.
In simple words: Polar winds are very cold and dry winds that move from the poles to sub-polar areas, blowing from north-east in the north and south-east in the south.

🎯 Exam Tip: Highlight their cold, dry nature, origin in polar regions, and general direction of movement towards lower latitudes.

 

Question 9. According to the modern concept, how does the autumnal monsoon arise?
Answer: According to the modern concept, the autumnal monsoon, also known as the rainy monsoon, is linked to a strong wind flow called the Jet Stream. This Jet Stream blows from west to east at a height of about 12 km in the troposphere. In winter, in the Northern Hemisphere, this high-level jet stream splits due to the Himalayas and the Tibetan Plateau. The main branch of the jet stream follows a cyclonic path over Afghanistan and Pakistan, and this movement helps create the rainy monsoon. The interaction between the topography and high-altitude winds plays a crucial role.
In simple words: The autumnal monsoon happens because of how the fast-moving Jet Stream interacts with big mountains like the Himalayas, especially its path over Afghanistan and Pakistan in winter.

🎯 Exam Tip: Focus on the role of the Jet Stream and the geographical obstruction of the Himalayas in the modern explanation of the monsoon.

 

Question 10. Explain the features of the Sirocco Winds.
Answer: The Sirocco winds have several distinct features and effects:
1. They are hot, dry, and sand-filled winds that blow northwards from the Sahara Desert towards the Mediterranean Sea.
2. These winds are known to cause "blood rain" because they pick up red desert sand, which then falls with the rain over southern Italy.
3. As the Sirocco winds descend along the northern slopes of the Atlas Mountains, their dryness and temperature increase, becoming even more intense.
4. These winds are called by different names in various places they affect.
5. Sirocco winds can have very damaging effects on vegetation, agriculture, and fruit plantations due to their extreme heat and dryness. They can quickly dehydrate crops and plants.
In simple words: Sirocco winds are hot, dry, sandy winds from the Sahara that cause "blood rain" and harm plants, getting hotter as they move over mountains.

🎯 Exam Tip: Key points for Sirocco are its origin (Sahara), characteristics (hot, dry, sandy), "blood rain" phenomenon, and negative impacts on agriculture.

RBSE Class 11 Physical Geography Chapter 13 Short Answer Type Questions (SA-II)

 

Question 1. Explain the sub - tropical high pressure belt.
Answer: The sub-tropical high-pressure belt is found in both the Northern and Southern Hemispheres, specifically between 30° and 35° latitude. This belt is characterized by consistently high temperatures, high air pressure, and clear, cloudless skies throughout the year. A major feature of this pressure belt is that most of the world's hot deserts are located on the western edges of continents within this zone. Air descends here, warming up and suppressing cloud formation.
In simple words: The sub-tropical high-pressure belt is a hot, high-pressure area between 30° and 35° latitude in both parts of the world, where many deserts are found.

🎯 Exam Tip: Remember the latitude range (30°-35°), high temperature, high pressure, clear skies, and its association with desert formation on continent western edges.

 

Question 2. Explain the seasonal changes taking place in the air pressure belts.
Answer: Air pressure belts do not stay in the same position all year round; they show seasonal changes. These shifts happen because of the sun's movement towards the Northern (summer solstice) and Southern (winter solstice) Hemispheres, and also due to differences in how land and water heat up. For example, when the sun is in the Northern Hemisphere during summer, these belts shift about 5° north from their usual position. When the sun is in the Southern Hemisphere during winter, they shift about 5° south. These shifts lead to seasonal variations in weather and climate globally.
In simple words: Air pressure belts move north or south by about 5 degrees depending on the season and the sun's position, causing seasonal weather changes.

🎯 Exam Tip: The key point is the 5° latitudinal shift of pressure belts with the sun's apparent movement, impacting global weather patterns.

 

Question 3. Explain vertical distribution of atmospheric pressure.
Answer: Pascal was the first to explain that air pressure decreases as you go higher in the atmosphere. The lower layers of the atmosphere have higher density because the weight of all the air above them presses down. This means both the air density and pressure are greater closer to Earth's surface. In contrast, the air in the upper layers is less dense and has lower pressure. The air thins out with altitude, causing pressure to drop. This decrease in pressure with elevation is not always uniform; it depends on factors like air density, water vapor content, and Earth's gravity.
In simple words: Air pressure drops as you go higher because the air gets thinner and less dense. The pressure is highest near the ground.

🎯 Exam Tip: Emphasize that atmospheric pressure decreases with altitude due to reduced air density and the weight of the air column above.

 

Question 4. Explain the features of the sea breezes.
Answer: Sea breezes are localized winds that occur during the day, especially in coastal areas. Here are their features:
1. During the day, land heats up faster than water due to sunlight. This creates a low-pressure area over the land and a high-pressure area over the cooler sea.
2. Winds start blowing from the sea towards the land, usually beginning around 10-11 a.m. and becoming strongest between 1-2 p.m.
3. Sea breezes typically end by 8 o'clock in the evening as the land cools down.
4. In tropical coastal areas, the arrival of sea breezes can significantly cool the temperature by 5-7°C within 15-20 minutes, making the weather pleasant and healthy. This natural cooling mechanism helps moderate coastal temperatures.
5. These winds can also bring moisture from the sea, leading to rainfall in coastal regions during the summer.
In simple words: Sea breezes happen during the day when land heats faster than the sea, causing cool winds to blow from the sea to the land, lowering temperatures and sometimes bringing rain.

🎯 Exam Tip: Remember that sea breezes are a daytime phenomenon driven by differential heating of land and water, bringing cooler temperatures and sometimes moisture to coasts.

 

Question 5. Explain the difference between Mountain Breeze and Valley Breeze.
Answer: The main differences between mountain breeze and valley breeze are outlined below. These two types of local winds are driven by daily heating and cooling cycles of mountain slopes:

In simple words: Mountain breezes flow down at night when slopes cool, and valley breezes flow up during the day when slopes warm.

🎯 Exam Tip: Clearly distinguish between the time of occurrence (day/night) and the direction of flow (upslope/downslope) for both breezes, linking them to temperature differences.

 

Question 6. Explain the difference between Harmattan and Mistral winds.
Answer: The differences between Harmattan and Mistral winds are highlighted below. These are two distinct types of local winds with different characteristics and impacts:

In simple words: Harmattan is a hot, dry African wind that makes humid weather better, while Mistral is a cold, dry wind in Europe that drops temperatures below freezing.

🎯 Exam Tip: Focus on the contrasting characteristics: Harmattan is hot and dry from Sahara, Mistral is cold and dry from mountains in Europe, and their different impacts on local climate.

RBSE CLASS 11 Physical Geography Chapter 13 Essay Type Questions

 

Question 1. Describe the condition and distribution of air pressure in January and July.
Answer: The distribution of air pressure across the globe changes significantly between January and July due to the seasonal shift in the sun's position and the varying heating properties of land and water. This creates distinct pressure patterns in different hemispheres.

Air Pressure in January:
In January, the sun shines almost directly over the Tropic of Capricorn in the Southern Hemisphere. This leads to high temperatures and lower air pressure in the Southern Hemisphere. Low-pressure areas develop over the interior landmasses of South America, South Africa, and Australia. Conversely, the continents in the Northern Hemisphere experience cooler temperatures and have well-developed sub-tropical high-pressure regions. The unequal heating of land and sea plays a crucial role in these pressure distributions.