Density of Population: The number of persons living per unit area, say per square kilometer on the average is called Density of Population. Example – 324 persons per square kilometer in India (2001 census)
Sex Ratio: The number of females per thousand of males is termed as sex ratio.
Birth Rate: Birth Rate refers to live births per thousand of persons every year.
Natural Growth Rate: The difference between birth rate and death rate of a country is known as Natural Growth Rate.
Life Expectancy: Life expectancy is the number of years for which an average man expects to live.
NCERT Textbook Exercise Questions (Important only)
(i) Why people are considered a resource?
(ii) What are the causes for the uneven distribution of population in the world?
(iii) The world population has grown very rapidly. Why?
(iv) Discuss the role of any two factors influencing population change.
(v) What is meant by population composition?
(vi) What are population pyramids? How do they help in understanding about the population of a country?
(i) People are considered a resource because with their demands and capabilities they can create new resources. Nature’s bounty becomes important only when people find it and make it useful for them. Hence, human resource is also considered an important and potential resource for the society.
(ii) The way in which people are distributed across the earth is known as the pattern of population distribution. Actually more than 90% of the world’s population lives in about 10% of the land surface. Some areas are over-crowded and some are sparsely populated. Following are the various factors responsible for this extremely uneven distribution of population in the world:
a. Geographical factors – Favourable topography, availability of mineral and fresh water resources, favourable climate and soil fertility are some of the reasons affecting population distribution e.g., Indo Gangetic Plains, Diamond Mines of South Africa etc are densely populated.
b. Social and Cultural factors – Areas of better housing, education and health facilities are more populated. Places of religious and cultural significance also attract people e.g., Varanasi, Jerusalem etc.
c. Economic factors – Places having more industries, transportation and communication facilities provide better employment opportunities. People are attracted to these places because of the above reasons e.g., Mumbai, Osaka etc.
(iii) The world population has grown very rapidly particularly after 1800s. The reasons are growth in food supplies, improvement in medical facilities, reduced death rate while the birth rate remained the same.
(iv) Birth rate, Death rate and Migration.
(v) Population composition refers to the structure of the population. Population composition helps to know the number of males or female, their age-groups, literacy, their occupation, their income level and health conditions etc.
(vi) The tapering figure of the population based on age and sex is termed as population pyramid. An interesting way of studying the population composition of a country is by studying at the population pyramid.
Short type Questions with their Answers
Q.1: Which hemisphere has more population?
Ans: Northern hemisphere.
Q.2: What is the average density of world population?
Ans: 45 persons per sq. km.
Q.3: Name the country with slowing growth rate of population.
Ans: United Kingdom.
Q.4: What are the people called who have come from other countries?
Q.5: What is Emigration?
Ans: Movement of people to other countries is called Emigration.
Long type Questions with their Answers
Q.1: Which are the geographical factors affecting the distribution of population?
Ans: The geographical factors affecting the distribution of population are:
(i) Topography – People generally prefer living on plains rather than on mountains or plateaus as these areas are suitable for farming and other similar activities.
(ii) Soil – People prefer to live in areas with fertile soil as it supports agriculture.
(iii) Climate – People avoid extreme climates.
(iv) Water – People prefer living in the areas where fresh water is easily available.
(v) Minerals – People are attracted towards the areas rich in mineral deposits.