CDS Geography · World and Human Geography
Population, Cities and Industry
The measures of population density and sex ratio, the population pyramid, the words NCERT uses for cities and settlements, and the cities and mines known for one industry.
Why this matters
Eleven CDS questions from 2017 to 2024: 1 EASY, 6 MODERATE, 4 HARD, the most HARD of any page in this chapter. Most test a term from NCERT's human geography (physiological density, primate city, gateway city), and two are city-and-industry match lists.
Concept 1 of 3: Density, sex ratio and the population pyramid
Every population measure is one number divided by another, and the name tells you which. Density divides people by land, so ask which land: all of it, or only the land that can be farmed. Sex ratio compares men and women, so ask which way round the country counts it.
Definition
Density (people per unit of land):
- Arithmetic density: total population ÷ total land area.
- Physiological density: total population ÷ arable (farmable) land. It shows the pressure of people on the land that feeds them.
- Agricultural density: farm population ÷ arable land.
Sex ratio (NCERT Class 12):
- In India it is females per 1,000 males. Some countries count it the other way, as males per 1,000 females.
- The world's sex ratio is about 102 males per 100 females. Asia has a low sex ratio: fewer women than men, as in China and India.
The population pyramid shows age groups up the side and males and females on either side. A wide base means many children, so a high birth rate. Language: most of Central Asia speaks Turkic languages (Uzbek, Kazakh, Kyrgyz, Turkmen) of the Altaic family.
| Term | How it is worked out or what it shows |
|---|---|
| Arithmetic density | Total population ÷ total land area |
| Physiological density | Total population ÷ arable land |
| Agricultural density | Farm population ÷ arable land |
| Sex ratio in India | Females per 1,000 males |
| Sex ratio of Asia | Low: fewer women than menQ CDS 2019 (II): the false statement was that Asia has a high sex ratio. |
| Population pyramid | Age groups and the two sexesQ CDS 2022 (I): it displays both age groups and sex. |
| Main language family of Central Asia | Altaic (Turkic languages)Q CDS 2020 (I): Altaic, not Indo-European or Sino-Tibetan. |
Practice this conceptself-check · 4 quick reps
The same idea in a real exam question:
CDS · 2020 · CDS (I) 2020 — General Knowledge · Q40Hard
Example 1 · World and Human Geography · Population, Cities and Industry
The number of people per unit area of arable land is termed as
Physiological is everyone; agricultural is farmers only
Both divide by arable land. Physiological density counts the whole population; agricultural density counts only the farm population. Arithmetic density uses all the land, not just arable land.
Low sex ratio means fewer women
When NCERT says Asia has a low sex ratio, it counts women per men: there are fewer women. Do not read 'low' as fewer men.
Concept 2 of 3: Cities and settlement patterns
Human geography names the shapes villages take and the jobs cities do. A village's shape follows whatever it is built along: a road, a river, a lake. A city's name in the textbook follows its role: the one giant city, the city at the country's door.
Definition
Settlement patterns (NCERT Class 12):
- Linear: along a road, railway, river or canal.
- Circular: around a lake or tank, with the houses facing the water.
- Cross-shaped: where two roads cross. Others are T-shaped, star-like and the double village on both banks of a river.
Kinds of city:
- Primate city: a country's largest city, many times bigger than the second. The idea is Mark Jefferson's (1939). Bangkok is a standard example.
- Central place theory is Christaller's, developed by Lösch.
- Gateway city: a city whose position links a country or region with others. It controls the entry and exit, so it dominates a wide area. Most are ports, and many were colonial capitals.
- London was the first city in the world to reach one million people, around 1810.
| Term | Meaning | Name to remember |
|---|---|---|
| Primate city | A country's largest city, far bigger than the second | Mark Jefferson (1939)Q CDS 2017 (II): Jefferson, not Christaller or Lösch. |
| Central place theory | How towns serve the area around them | Christaller; Lösch |
| Gateway city | Links a country or region with the outside; most are ports | Many were colonial capitalsQ CDS 2024 (I): all three statements about gateway cities were correct. |
| First million city | The first city to reach one million people | London, around 1810Q CDS 2022 (I): London, not Paris or New York. |
| Linear settlement | Houses along a road, river or canal | Follows the line |
| Circular settlement | Houses around a lake or tank | Faces the water |
| Cross-shaped settlement | Houses where two roads meet | Grows four ways |
Practice this conceptself-check · 4 quick reps
The same idea in a real exam question:
CDS · 2023 · CDS (II) 2023 — General Knowledge · Q27Moderate
Example 2 · World and Human Geography · Population, Cities and Industry
Which one of the following forms of settlement develops around a lake ?
Jefferson, not Christaller
The primate city belongs to Mark Jefferson. Christaller and Lösch gave central place theory, and Griffith Taylor a stage theory of towns; all three are offered as distractors.
London, not Paris or New York
London reached one million people first, around 1810. Paris and New York came later.
Concept 3 of 3: Industrial regions and famous mines
These are match lists: a city or region against a country or a product. Each place is known for one thing, so learn them as pairs and the code falls out after two certain matches.
Definition
Industrial places CDS has asked:
- Detroit (Michigan, USA): motor cars.
- Leipzig (Saxony, Germany): an old industrial and trading city.
- Lorraine (France): iron ore and steel.
- Cumberland (north-west England, UK): an old coal and iron district.
- Antwerp (Belgium): diamond cutting.
- Tokyo and Yokohama (Japan): shipbuilding, among other heavy industry.
- Harbin (north-east China): heavy industry; matched with steel in the 2019 (I) list.
- The Climax mine in the Colorado Rockies, USA, was for decades the world's leading source of molybdenum.
| Place | Country | Known for |
|---|---|---|
| Detroit | USA | Motor cars |
| Leipzig | Germany | Old industrial and trading city |
| Lorraine | France | Iron ore and steel |
| Cumberland | UK | Old coal and iron district |
| Antwerp | Belgium | Diamond cuttingQ CDS 2019 (I) match: Detroit motor cars, Antwerp diamond cutting, Tokyo shipbuilding, Harbin steel. |
| Tokyo and Yokohama | Japan | Shipbuilding |
| Climax mine | USA (Colorado) | MolybdenumQ CDS 2020 (II): the Climax mine is in the USA, not Canada. |
Practice this concept3 quick reps
The same idea in a real exam question:
CDS · 2017 · CDS (II) 2017 — General Knowledge · Q81Moderate
Example 3 · World and Human Geography · Population, Cities and Industry
Match List-I with List-II and select the correct answer using the code given below the Lists :
Code :
| List-I (Industrial Region) | List-II (Country) |
|---|---|
| A. Leipzig | 1. USA |
| B. Detroit | 2. UK |
| C. Lorraine | 3. France |
| D. Cumberland | 4. Germany |
Cumberland is English
The Cumberland of the industrial match list is the old coal and iron district of north-west England, not a place in the United States.
Climax is in Colorado
The Climax molybdenum mine is in the Rocky Mountains of Colorado, USA. Canada, Australia and South Africa are offered because they are big mining countries too.
Summary — formulas & gotchas at a glance
A revision cheat-sheet for the formulas and gotchas above. Click any concept name to jump back to its full explanation.
Reference tables (3)
Density, sex ratio and the population pyramid7 rows
| Term | How it is worked out or what it shows |
|---|---|
| Arithmetic density | Total population ÷ total land area |
| Physiological density | Total population ÷ arable land |
| Agricultural density | Farm population ÷ arable land |
| Sex ratio in India | Females per 1,000 males |
| Sex ratio of Asia | Low: fewer women than menQ CDS 2019 (II): the false statement was that Asia has a high sex ratio. |
| Population pyramid | Age groups and the two sexesQ CDS 2022 (I): it displays both age groups and sex. |
| Main language family of Central Asia | Altaic (Turkic languages)Q CDS 2020 (I): Altaic, not Indo-European or Sino-Tibetan. |
Cities and settlement patterns7 rows
| Term | Meaning | Name to remember |
|---|---|---|
| Primate city | A country's largest city, far bigger than the second | Mark Jefferson (1939)Q CDS 2017 (II): Jefferson, not Christaller or Lösch. |
| Central place theory | How towns serve the area around them | Christaller; Lösch |
| Gateway city | Links a country or region with the outside; most are ports | Many were colonial capitalsQ CDS 2024 (I): all three statements about gateway cities were correct. |
| First million city | The first city to reach one million people | London, around 1810Q CDS 2022 (I): London, not Paris or New York. |
| Linear settlement | Houses along a road, river or canal | Follows the line |
| Circular settlement | Houses around a lake or tank | Faces the water |
| Cross-shaped settlement | Houses where two roads meet | Grows four ways |
Industrial regions and famous mines7 rows
| Place | Country | Known for |
|---|---|---|
| Detroit | USA | Motor cars |
| Leipzig | Germany | Old industrial and trading city |
| Lorraine | France | Iron ore and steel |
| Cumberland | UK | Old coal and iron district |
| Antwerp | Belgium | Diamond cuttingQ CDS 2019 (I) match: Detroit motor cars, Antwerp diamond cutting, Tokyo shipbuilding, Harbin steel. |
| Tokyo and Yokohama | Japan | Shipbuilding |
| Climax mine | USA (Colorado) | MolybdenumQ CDS 2020 (II): the Climax mine is in the USA, not Canada. |
Watch out for (6)
- Physiological is everyone; agricultural is farmers only→ Density, sex ratio and the population pyramid
- Low sex ratio means fewer women→ Density, sex ratio and the population pyramid
- Jefferson, not Christaller→ Cities and settlement patterns
- London, not Paris or New York→ Cities and settlement patterns
- Cumberland is English→ Industrial regions and famous mines
- Climax is in Colorado→ Industrial regions and famous mines
Test yourself on World and Human Geography
15 past CDS questions from this chapter, timed at 15 minutes and marked the way the exam marks it. You see your score and every answer the moment you finish. Free to start.