Population Growth

Correct answer: A. In-migration is very high in an industrial town because of jobs

Direct answer: A is correct. A national average combines the figures of many different places, so it can hide local differences. Consider an industrial town step by step. New factories and services create jobs. Workers from other places may move into the town, producing high in-migration. The town’s population may therefore grow faster than the country’s average, even if birth rates are falling. Other areas may grow slowly, remain stable, or lose people through out-migration. B is wrong because equal growth would not create a difference from the average. C is not a meaningful explanation of a local growth pattern and does not describe a normal populated locality. D is wrong because the absence of a census creates a data problem; it does not itself cause a different growth rate. Always compare scale and place: national, regional, and local figures may tell different stories.

Correct answer: A. Growth is a change in number and sex ratio gives the male-female ratio

Direct answer: A is correct. Population growth and sex ratio describe different features of a population. First, population growth means a change in the total population over a period of time. The change can result from births, deaths, and migration. Second, sex ratio compares the numbers of females and males. In Indian demographic usage, it is commonly expressed as the number of females per 1,000 males. Thus, growth answers “How is the total number changing?” while sex ratio answers “How are females and males represented relative to each other?” B is wrong because these are separate indicators. C is wrong because sex ratio is not land area or a physical measurement. D is wrong because population growth concerns the total population, not males alone. A correctly keeps the concepts separate. Memory cue: growth is change through time; sex ratio is comparison between sexes.

Correct answer: A. Initial population, final population, births, deaths, migration, and time period

Direct answer: A is correct. To study population growth, we need data showing the population at two points in time and the processes that change it. The initial population gives the starting number, while the final population gives the later number. Births add people, deaths reduce the number, and migration can add people to or remove people from an area. The time period is essential because a change has meaning only when we know how long it took; it also allows comparison of growth rates. This data can help describe both the amount and the possible causes of change. B concerns physical geography, C concerns soil and crops, and D describes cultural characteristics. Those data may be useful for other studies, but they do not directly measure population growth. Memory cue: population change = starting number, ending number, births, deaths, migration, and time.

Correct answer: C. 4%

Direct answer: C, 4%. First find the absolute increase: 26,000 − 25,000 = 1,000 people. Growth rate is calculated by dividing the increase by the initial population and multiplying by 100. Therefore, growth rate = (1,000 ÷ 25,000) × 100 = 4%. The initial population must be used as the denominator because the question asks how much the population increased compared with its starting size. A would represent an increase of only 500 people, B an increase of 750 people, and D an increase of 1,250 people on this base. None matches the actual increase of 1,000. Do not divide by the final population unless a different measure is specifically requested. Memory cue: percentage growth = increase ÷ old value × 100.

Correct answer: A. 1.2 lakh

Direct answer: A, 1.2 lakh. Absolute increase is found by applying the percentage rate to the base population. Convert 1.5 percent into a fraction: 1.5/100 = 0.015. The base population is 80 lakh, so absolute increase = 0.015 × 80 lakh = 1.2 lakh. The new population, if required, would be 80 + 1.2 = 81.2 lakh; the question asks only for the increase. Option A is correct. Option B, 12 lakh, comes from multiplying incorrectly by a much larger rate. Option C, 81.5 lakh, incorrectly treats the rate as 1.5 lakh added directly and also gives a total rather than the increase. Option D, 0.15 lakh, misses a factor of ten. Memory cue: percentage increase = rate divided by 100 multiplied by the original population.

Correct answer: B. 10 percent

Direct answer: B, 10 percent, is correct. First find the absolute increase: 165 lakh − 150 lakh = 15 lakh. Percentage growth is calculated by dividing the increase by the original population and multiplying by 100: (15 ÷ 150) × 100 = 0.1 × 100 = 10 percent. The original population must be used as the denominator, not the final population. A is wrong because 15 lakh is the absolute increase, not the percentage; 5 percent of 150 lakh would be only 7.5 lakh. C is wrong because it confuses the increase of 15 lakh with 15 percent. D is wrong because 20 percent of 150 lakh would be 30 lakh, which is not the increase. Memory cue: percentage growth = (new value − old value) ÷ old value × 100.

Correct answer: B. Total population can grow even if a positive rate declines

Direct answer: Option B is correct. Population size is the total number of people, whereas the growth rate is the speed or percentage at which that number changes. If the rate remains positive, the population continues to increase even when the rate becomes smaller. For example, growth of 3% followed by growth of 1% still adds people; it means the increase is slower, not that the total has fallen. Option A is wrong because a declining rate becomes population decline only when the rate is negative, or when deaths and out-migration exceed births and in-migration. Option B correctly describes a slowing positive increase. Option C is wrong because population size depends on births, deaths and migration as well as area. Option D is wrong because rate and size are related, although they are not identical measures. Memory cue: falling speed does not mean moving backward.

Correct answer: C. Absolute growth

Direct answer: Option C is correct. In this notation, P₁ means the population at the earlier time and P₂ means the population at the later time. Subtracting P₁ from P₂ gives the actual numerical change in the number of people: absolute growth = P₂ − P₁. For example, if a town increases from 10,000 to 12,000 people, its absolute growth is 2,000 people. Option A is wrong because an annual percentage rate requires comparison with the base population and a time period, usually expressed as a percentage. Option B is wrong because natural increase is births minus deaths and does not by itself include migration. Option D is wrong because density is population divided by area. Memory cue: subtraction gives the number added; division by the base and multiplication by 100 gives a percentage.

Correct answer: A. (P₂ − P₁) / P₁ × 100 / (P₂ − P₁) / P₁ × 100

Direct answer: Option A is correct. Population growth rate expresses the change in population as a percentage of the earlier or base population. If P₁ is the initial population and P₂ is the later population, the formula is (P₂ − P₁) ÷ P₁ × 100. First subtract the earlier population from the later one to find the change. Then divide that change by the initial population, and finally multiply by 100 to convert it into a percentage. Option B reverses the basic quantities and is not a growth-rate formula; population divided by area is related to density. Option C compares deaths with births and does not calculate population growth rate. Option D uses unrelated variables and has no demographic meaning. Memory cue: change ÷ starting population × 100; the denominator is the base population, not area.

Correct answer: A. Due to rising demand for land, water, energy, and waste management

Correct answer: A. Rapid population growth means that more people need homes, food, water, energy, transport, and public services. Step by step, a larger population can increase the demand for land and freshwater; producing and transporting more goods can require more energy; and more households and industries can produce more solid waste and wastewater. If resources are not managed carefully, this may cause pollution, pressure on forests, soil, rivers, and groundwater, and greater difficulty in waste disposal. A is correct because it clearly describes the population–resource–environment connection. B is wrong because population growth does not stop Earth’s rotation. C is wrong because the Moon’s size is unrelated to population change. D is wrong because forests do not automatically increase and may even be cleared for settlements or farming. Memory cue: more people can mean more resource demand and more waste, though good planning can reduce the pressure.

Correct answer: A. A high birth rate can be a cause and resource pressure can be a consequence

Correct answer: A. Population change results from demographic processes, especially births, deaths, and migration. A high birth rate can contribute to natural increase and therefore may be one cause of population growth. If the number of people rises, demand for food, water, housing, energy, schools, health care, and transport may also rise; this can create resource and service pressure as a consequence. A is correct because it keeps the direction of cause and effect clear. B is wrong because resource pressure is not a formula for birth rate; it may influence decisions, but it is not the definition of the rate. C is wrong because population growth has identifiable causes. D is wrong because death rate is a demographic process or measure, not simply a consequence. Memory cue: ask “what produces the change?” for causes and “what follows the change?” for consequences.

Correct answer: A. When population rises fast and health services do not expand at the same pace

The correct answer is A. A health system has limited capacity, including doctors, nurses, clinics, hospitals, medicines, beds and emergency services. When the number of people increases faster than this capacity, each facility or health worker may have to serve more people. Waiting time can rise and access to preventive care, treatment and maternal or child services may become more difficult. The exact effect also depends on distribution and quality, but the mismatch between population growth and service expansion creates the greatest pressure among these choices. B is wrong because services growing faster generally improve capacity per person. C does not necessarily create rapid population growth or extra pressure. D describes a stable population and zero migration, not the strongest growth pressure. Memory cue: pressure rises when population grows faster than service capacity.

Correct answer: A. Because teachers and schools may be insufficient as student numbers rise

The correct answer is A. Rapid population growth can increase the number of children who need schooling. If new schools, classrooms, teachers, textbooks, toilets and learning materials are not added at a similar rate, existing facilities must serve more students. Class sizes may become larger, teachers may have less time for each learner and the amount of space or material available per student may fall. These conditions can affect educational quality, although good planning and investment can reduce the pressure. Option A is correct because it explains the connection between rising student numbers and limited educational capacity. B is wrong because population size directly affects school demand. C is wrong because birth rate does not literally close schools. D is wrong because migration may change enrolment numbers or language needs, but it does not automatically change the syllabus. Memory cue: more children require more educational capacity, not merely more admissions.