NCERT Solutions For Class 8 Social Science Chapter 8
Mineral and Power Resources

When people are attracted to an area it becomes densely populated.
Factors that influence this include favourable climate; good supplies of natural resources and fertile land.

(i) (c) The way in which people are spread across a given area.  ✓
(ii) (b) Births, deaths and migration  ✓
(iii) (c) 6 billion  ✓
(iv) (a) A graphical presentation of the age, sex composition of a population. ✓

(i) People are a nation’s greatest resource. Nature’s bounty becomes significant only when people find it useful. They can make the best use of nature to create more resources as they have the knowledge, skill and the technology to do so. It is people with their demands and abilities that turn them into ‘resources’. Education and health help in making people a valuable resource.

(ii) The distribution of population in the world is extremely uneven. The factors responsible for uneven distribution of population are:
1. Geographical factors: Favourable topography and climate, fertile soil, availability of water and mineral resources affect population distribution.
2. Social factors: Areas of better housing, education and health facilities are more densely populated.
3. Cultural factors: Places with religion or cultural significance attract people.
4. Economic factors: Places with more industries, transport and communication facilities, and better employment opportunities attract more people.

(iii) The world population has grown very rapidly. The population increase in the world is mainly due to the rapid increase in the natural growth rate. The main reason for this growth was that with better food supplies and medicine, deaths were reduced, while the number of births still remained fairly high.

(iv) Two factors influencing population change are natural growth and migration.
1. The difference between the birth rate and the death rate of a country is called the natural growth rate. The birth rate is the number of live births per 1,000 people. The death rate is the number of deaths per 1,000 people. Births and deaths are the natural causes of population change.
2. Population size also changes due to migration. Migrations are the movement of people in and out of an area. People may move within a country or between countries. Immigration is people coming from neighbouring countries. Emigration is people moving to other countries.

(v) Population composition refers to the structure of the population. Population composition helps to know about the individual characteristics, like gender, age group, literacy level, occupation, income and health conditions.

(vi) Population composition of a country is represented by the population pyramid or age-sex pyramid. The Population pyramid shows the age-sex structure of the population. The pyramid displays the percentage or actual amount of a population, broken down by gender and age. By studying the population pyramid, we can understand the various parameters of the population of a country. Different shapes of the pyramid reflect the number of people of different age and sex. A population pyramid shows:
1. The total population divided into various age groups.
2. In each of the groups, the percentage of the total population is subdivided into males and females.
3. Number of dependents in a country and people in the working category.
4. Levels of births and deaths.