Population: Class 9 Study Guide
People are a country's greatest resource. Their number, age and skills shape its future.
India's population was about 1.21 billion at the 2011 Census, the most recent full count in the textbooks. India is the most populous country, so planning for food, schools, health and jobs matters.
The study of population looks at size, distribution (where people live), density (people per square kilometre), growth, and the make-up of the population.
Key measures
| Term | Meaning |
|---|---|
| Population density | Number of people per square kilometre |
| Birth rate | Births per thousand people in a year |
| Death rate | Deaths per thousand people in a year |
| Migration | Movement of people from one place to another |
| Sex ratio | Females per thousand males |
| Literacy rate | Share of people who can read and write |
Growth and make-up
Population grows when births exceed deaths. India's growth was slow until 1921, then rose quickly after better health care reduced deaths. The population can be grouped by age: children (0 to 14), working age (15 to 59) and older people (60 and over). A large share of working-age people can be an advantage if they have education and jobs. The government's national population policy aims at healthy families and better education, especially for girls.
Worked examples and common mistakes
Example: A state has 4,00,000 people in 1,000 sq km. Density = 4,00,000 ÷ 1,000 = 400 people per sq km. Example: Why did growth speed up after 1921? Deaths fell faster than births. Common mistakes: confusing density with total population, and writing the sex ratio as males per thousand females.
Check your understanding: model answers
1. People per square kilometre. 2. Females per thousand males. 3. There are many people of working age.
✨ Key Takeaways
- India's population is very large.
- Density is people per square kilometre.
- Growth depends on births, deaths and migration.
- Education and health make people a resource.
💬 Questions for Discussion & Reflection
- Define population density.
- What is the sex ratio?
- Why can a young population be an advantage?