What will happen if we kill all
[question] Question. What will happen if we kill all the organisms in one trophic level ? [/question] [solution] solution: If we kill all the organisms in one trophic level then transfer of energy as well as matter to next higher level will stop. It will lead to over population at lower trophic level causing competition amongst the individuals. This would seriously disturb the food chain and can cause even a collapse of an ecosystem. [/solution]...
Read More →Every village in India is surveyed once in ten years during the Census and some of the details are presented in the following format.
[question] Question. Every village in India is surveyed once in ten years during the Census and some of the details are presented in the following format. Fill up the following based on information on Palampur. a. LOCATION: b. TOTAL AREA OF THE VILLAGE: c. LAND USE (in hectares): d. FACILITIES: [/question] [solution] Solution: a. LOCATION: Bulandshahar district, Western Uttar Pradesh b. TOTAL AREA OF THE VILLAGE: 226 hectares c. LAND USE (in hectares): d. FACILITIES: [/solution]...
Read More →Explain the working and applications of a sonar.
[question] Question. Explain the working and applications of a sonar. [/question] [solution] Solution: Refer theory, page no.71. [/solution]...
Read More →Which of the following are environment friendly practices ?
[question] Question. Which of the following are environment friendly practices ? (a) Carrying cloth-bags to put purchases in while shopping (b) Switching off unnecessary lights and fans (c) Walking to school instead of getting your mother to drop you on her scooter (d) All of the above. [/question] [solution] solution: (d) All of the above. [/solution]...
Read More →How is ultrasound used for cleaning ?
[question] Question. How is ultrasound used for cleaning ? [/question] [solution] Solution: The object to be cleaned is put in a tank fitted with ultrasonic vibrator. The tank is filled with water containing detergent. As the ultrasonic vibrator is switched on, the detergent rubs against the object at a very high speed and hence cleans it. [/solution]...
Read More →Using examples from your area compare and contrast the activities and functions of private and public sectors.
[question] Question. Using examples from your area compare and contrast the activities and functions of private and public sectors. [/question] [solution] Solution: Attempt this question on your own. [/solution]...
Read More →Explain how bats use ultrasound to catch their prey
[question] Question. Explain how bats use ultrasound to catch their prey [/question] [solution] Solution: The bats produce high pitched ultrasonic waves which are not heard by human beings. The ultrasonic waves on striking the insect send back an echo, which is heard by the bat. As the echo is heard by the bat, it moves towards the insect and catches it. [/solution]...
Read More →What are the significant features of the National Population Policy 2000?
[question] Question. What are the significant features of the National Population Policy 2000? [/question] [solution] Solution: The National Population Policy 2000 provides a policy framework for: (i) Imparting free and compulsory school education up to 14 years of age (ii) Reducing infant mortality rate to below 30 per 1000 live births (iii) Achieving universal immunisation of children against all vaccine-preventable diseases (iv) Promoting delayed marriage and child bearing (v) Making family w...
Read More →Which of the following constitute food-chain ?
[question] Question. Which of the following constitute food-chain ? (a) Grass, wheat and mango (b) Grass, goat and human (c) Goat, cow and elephant (d) Grass, fish and goat. [/question] [solution] solution: (b) Grass, goat and human [/solution]...
Read More →Explain the objective of implementing the NREGA 2005.
[question] Question. Explain the objective of implementing the NREGA 2005. [/question] [solution] Solution: The objective of implementing the NREGA 2005 was to provide 100 days of guaranteed employment to those people in rural India who can work, and are in need of work. This Right to Work has been implemented in 200 districts. If the government is unable to provide this employment, then it has to give unemployment allowances to the people. [/solution]...
Read More →Which of the following groups contain only biodegradable items?
[question] Question. Which of the following groups contain only biodegradable items? (a) Grass, flowers and leather (b) Grass, wood and plastic (c) Fruit-peels, cake and lime-juice (d) Cake, wood and grass [/question] [solution] solution: (c) Fruit-peels, cake and lime-juice (d) Cake, wood and grass [/solution]...
Read More →What are the advantages of having a healthy population?
[question] Question. What are the advantages of having a healthy population? [/question] [solution] Solution: Health is an important component of population which affects the process of development. A healthy population is an asset to the country. A healthy individual is much more efficient and productive than an unhealthy individual. He or she is able to realise his or her potential, and play an important role in social and national development. [/solution]...
Read More →What is loudness of sound ? What factors does it depend on ?
[question] Question. What is loudness of sound ? What factors does it depend on ? [/question] [solution] Solution: The loudness of the sounds humans perceive relates to the intensity of the audible sound. Loudnessis a subjective property of the sound that depends on the human ear, the sensitivity of the ear to the frequency of the sound, and the distance from the source of the sound. Loudness of the sound depends inversely on the square of the distance of the observer from the source of sound, a...
Read More →Compare the employment conditions prevailing in the organised and unorganised sectors.
[question] Question. Compare the employment conditions prevailing in the organised and unorganised sectors. [/question] [solution] Solution: The employment conditions prevailing in the organised and unorganised sectors are vastly different. The organised sector has companies registered with the government and hence, it offers job security, paid holidays, pensions, health and other benefits, fixed working hours and extra pay for overtime work. On the other hand, the unorganised sector is a host o...
Read More →What is the relation between occupational structure and development?
[question] Question. What is the relation between occupational structure and development? [/question] [solution] Solution: The distribution of the population according to the different types of occupations is referred to as the occupational structure. Occupations are generally classified as primary (agriculture, mining, fishing, etc.), secondary (manufacturing industry, building and construction work, etc.) and tertiary (transport, communications, banking, etc.). The proportion of people working...
Read More →How can you help idegradable and non
[question] Question. How can you help idegradable and non biodegradable waste before dumping [/question] [solution] solution: To reduce the problem of waste disposal we can :- (i) Segregate the biodegradable and non biodegradable waste before dumping (ii) Remove all materials which can be recycled. eg paper, glass. [/solution]...
Read More →What is reverberation ? How can it be reduced ?
[question] Question. What is reverberation ? How can it be reduced ? [/question] [solution] Solution: Reverberation is the repeated/multiple reflections of sound in any big enclosed space. It can be reduced by covering the ceiling and walls of the enclosed space with some sound-absorbing materials like fibre board, loose woolens etc. [/solution]...
Read More →Distinguish between population growth and population change.
[question] Question. Distinguish between population growth and population change. [/question] [solution] Solution: [/solution]...
Read More →What is ozone and how does
[question] Question. What is ozone and how does it affect any ecosystem? [/question] [solution] solution: (i) Ozone is formed in atmosphere by the action of ultraviolet radiation on oxygen gas. (ii) The high energy ultraviolet radiation (UV radiation) coming from the sun splits oxygen gas into free oxygen atoms (iii) The free oxygen atoms are highly reactive. One oxygen atom reacts with an oxygen molecule to form an ozone molecule. $\mathrm{O}_{2}+\mathrm{O} \longrightarrow \mathrm{O}_{3}$ (Ozon...
Read More →How are the activities in the economy classified on the basis of employment conditions?
[question] Question. How are the activities in the economy classified on the basis of employment conditions? [/question] [solution] Solution: On the basis of employment conditions, activities in the economy are classified as organised and unorganised. The organised sector offers job security and employment benefits, while the unorganised sector is marked by low wages and lack of job security. In rural areas, the unorganised sector comprises landless agricultural labourers, sharecroppers and arti...
Read More →A sound wave travels at a speed of 339 ms–1.
[question] Question. A sound wave travels at a speed of 339 ms–1. If its wavelength is 1.5 cm, what is the frequency of the wave? Will it be audible ? [/question] [solution] Solution: Speed of sound wave, $\mathrm{v}=339 \mathrm{~ms}^{-1}$; Wavelength, $\lambda=1.5 \mathrm{~cm}=0.015 \mathrm{~m}$; Frequency, $v=?$ Frequency, $v=\frac{v}{2}=\frac{339}{0}=22600 \mathrm{~Hz}$ The sound will not be audible, because human beings can hear only up to $20,000 \mathrm{~Hz}$. [/solution]...
Read More →Answer the following questions briefly.
[question] Question. Answer the following questions briefly. (i) Why is the rate of population growth in India declining since 1981? (ii) Discuss the major components of population growth. (iii) Define age structure, death rate and birth rate. (iv) How is migration a determinant factor of population change? [/question] [solution] Solution: (i) Since 1981, birth rates have been declining gradually. As a result, there has been a gradual decline in the rate of population growth. (ii) The major comp...
Read More →Workers are exploited in the unorganised sector. Do you agree with this view?
[question] Question. Workers are exploited in the unorganised sector. Do you agree with this view? Give reasons in support of your answer. [/question] [solution] Solution: Workers are exploited in the unorganised sector. I agree with this view. The unorganised sector does not offer any job security. Neither does it allow for scope of trade or workers’ unions. Workers can be easily exploited in this scenario. They cannot afford to rebel against an employer’s tyranny as the latter can fire them at...
Read More →What is the role of decomposers
[question] Question. What is the role of decomposers in the ecosystem? [/question] [solution] solution: Decomposers are essential components of ecosystem. They decompose dead remains of plants and animals and their waste organic products into simpler, inorganic substances. The latter are released into the environment for their reuse as raw materials by the producers. Thus it maintains balance in nature and play important role in ecosystem. [/solution]...
Read More →Choose the right answer from the four alternatives given below.
[question] Question. Choose the right answer from the four alternatives given below. (i) Migrations change the number, distribution and composition of the population in (a) The area of departure (c) Both the area of departure and arrival (b) The area of arrival (d) None of the above (ii) A large proportion of children in a population is a result of (a) high birth rates (c) high death rates (b) high life expectancies (d) more married couples (iii) The magnitude of population growth refers to (a) ...
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