Question

How is density of population usually measured?
A) Person per sq km
B) The number of people in country
C) The number of households in country
D) The number of births from one census to the next in a country

Answer 1

Hint: The ratio between the land area and the people living above it is the population density. It is the number of individuals per area unit. One of the options is known as total population. Two of the options don't have any relation with measurement of population.

Complete answer:
The population density is commonly measured as the number of people per square kilometre.
The most widely used measure of population density is crude density, also known as arithmetic density. It is expressed as the number of individuals separated by the total area. As per the most recent 2001 census, India, for example, has an average density of 324 people per square kilometre. For rural and urban areas, crude or arithmetic density may be carried out separately. Crude density, being an average number, suffers from a major limitation.

Now lets see our options :
A) Person per sq km : The population density is commonly measured as the number of people per square kilometre. Thus this is the right option.
B) The number of people in country : the number of people in country is termed as population,not population density thus this option is wrong
C) The number of households in a country : households can be used to measure population density thus this option is wrong too.
D) The number of births from one census to the next in a country : The population density is commonly measured as the number of people per square kilometre. Thus this option is wrong too.

Hence the correct answer is option ‘A’.

Note: The population of the planet is around 7,500,000,000 and the total area of the Earth (including land and water) is 510,000,000 km2 (197,000,000 sq. mi.) The global human population density is thus around 7,500,000,000 ÷ 510,000,000 = 14.7 per km2 (38 per sq. mi.). India's population density was 382 per sq km in 2011. The population density was reduced between 2001 and 2011. Delhi NCT is the most heavily populated UT with a population density of 11, 297.