Give an account of weather conditions and characteristics of the cold season.
[question] Question. Give an account of weather conditions and characteristics of the cold season. [/question] [solution] Solution: The Cold Weather Season Beginning from mid-November, the winter season lasts till February. The weather is usually marked by clear sky, low temperatures and low humidity, and feeble and variable winds. The temperature decreases from the south to the north, with the peninsular region not showing any noticeable seasonal change in temperature pattern due to the moderat...
Read More →Discuss the mechanism of monsoons.
[question] Question. Discuss the mechanism of monsoons. [/question] [solution] Solution: During summer, a low-pressure area develops over interior Asia as well as over north and north-western India. At the same time, there is a high-pressure system over the southern Indian Ocean. Winds move from a high-pressure area to a low-pressure area. As a result, the low-pressure system attracts the southeast trade winds of the southern hemisphere. On crossing the equator, these trade winds—due to the Cori...
Read More →Which of the following is not an example
[question] Question. Which of the following is not an example of bio-mass energy source ? (a) wood (b) gobar gas (c) atomic energy (d) coal [/question] [solution] solution: Option (c) atomic energy is correct. [/solution]...
Read More →Describe the regional variations in the climatic conditions of India with the help of suitable examples.
[question] Question. Describe the regional variations in the climatic conditions of India with the help of suitable examples. [/question] [solution] Solution: Despite the overall unity accorded by the monsoon, there are visible regional variations in climatic conditions within India. Regardless of the moderating influences of the Himalayas in the north and the sea in the south, variations do exist in temperature, humidity and precipitation. For example, in summer, some parts of the Rajasthan des...
Read More →List a few examples of environmental degradation that you may have observed around you.
[question] Question. List a few examples of environmental degradation that you may have observed around you. [/question] [solution] Solution: Environmental degradation manifests itself in different ways. Deforestation, falling levels of ground water, soil erosion, water pollution, burning of fossil fuels, the hole in the ozone layer and combustion from automobiles causing extreme air pollution especially in urban areas are some of the examples of environmental degradation. [/solution]...
Read More →What is the range of frequencies associated with
[question] Question. What is the range of frequencies associated with (a) Infrasound ? (b) Ultrasound ? [/question] [solution] Solution: (a) Infrasound : Sound waves of frequencies between 1 to 20 Hz. (b) Ultrasound : Sound waves of frequencies above 20,000 Hz. [/solution]...
Read More →Give reasons as to why.
[question] Question. Give reasons as to why. (i) Seasonal reversal of wind direction takes place over the Indian subcontinent? (ii) The bulk of rainfall in India is concentrated over a few months. (iii) The Tamil Nadu coast receives winter rainfall. (iv) The delta region of the eastern coast is frequently struck by cyclones. (v) Parts of Rajasthan, Gujarat and the leeward side of the Western Ghats are drought-prone. [/question] [solution] Solution: (i) The seasonal reversal of wind direction ove...
Read More →"The Earth has enough resources to meet the needs of all but not enough to satisfy the greed of even one person".
[question] Question. "The Earth has enough resources to meet the needs of all but not enough to satisfy the greed of even one person". How is this statement relevant to the discussion of development? Discuss. [/question] [solution] Solution: “The Earth has enough resources to meet the needs of all but not enough to satisfy the greed of even one person”. This statement is relevant to the discussion of development since both resources and development go hand in hand. For the sustainability of deve...
Read More →Why does the rainfall decrease from the east to the west in Northern India?
[question] Question. Why does the rainfall decrease from the east to the west in Northern India? [/question] [solution] Solution: The amount of rainfall decreases from east to west in Northern India because of the progressive decrease in the humidity of the winds. As the moisture-bearing winds of the Bay of Bengal branch of the southwest monsoon move further and further inland, they exhaust most of the moisture they carry along with them. This consequently leads to a gradual decrease in the amou...
Read More →Answer the following questions briefly.
[question] Question. Answer the following questions briefly. (i) What are the controls affecting the climate of India? (ii) Why does India have a monsoon type of climate? (iii) Which part of India does experience the highest diurnal range of temperature and why? (iv) Which winds account for rainfall along the Malabar Coast? (v) What are jet streams and how do they affect the climate of India? (vi) Define monsoons. What do you understand by “break” in monsoon? (vii) Why is the monsoon considered ...
Read More →Why is the issue of sustainability important for development?
[question] Question. Why is the issue of sustainability important for development? [/question] [solution] Solution:. The issue of sustainability is important for development because development must be in tandem with the future. If natural resources are not sustained, then development will stagnate after a point of time. Exploiting resources unethically will ultimately undo the development that a country may have achieved. This is because in the future, those resources will not be available for ...
Read More →A solar water heater cannot be used to get hot water on
[question] Question. A solar water heater cannot be used to get hot water on (a) a sunny day (b) a cloudy day (c) a hot day (d) a windy day [/question] [solution] solution: Option (b) a cloudy day is correct. On cloudy day, heat radiations coming from the Sun do not reach the solar water heater. [/solution]...
Read More →What is the audible range of the average human ear ?
[question] Question. What is the audible range of the average human ear ? [/question] [solution] Solution: An average human ear can hear sound waves of frequencies between 20 Hz to 20,000 Hz. [/solution]...
Read More →Find out the present sources of energy that are used by the people in India.
[question] Question. Find out the present sources of energy that are used by the people in India. What could be the other possibilities fifty years from now? [/question] [solution] Solution: The present sources of energy that are used by the people of India are electricity, coal, crude oil, cowdung and solar energy. Other possibilities fifty years from now, could include ethanol, bio-diesel, nuclear energy and a better utilisation of wind energy, especially with the imminent danger of oil resour...
Read More →Why is the ceiling of concert halls curved ?
[question] Question. Why is the ceiling of concert halls curved ? [/question] [solution] Solution: The ceiling of concert halls is curved so that sound after reflection from it reaches all the corners of the hall and is audible to every person in the hall. [/solution]...
Read More →Give the names of two energy sources that you would consider to be exhaustible.
[question] Question. Give the names of two energy sources that you would consider to be exhaustible. Give reasons for your choices. [/question] [solution] solution: (1) Coal (2) Petroleum Both these sources are present only in limited amounts and will be exhausted soon if we continue to use them at the present rate. These sources were formed over millions of years under special circumstances. [/solution]...
Read More →Kerala, with lower per capita income has a better human development ranking than Punjab.
[question] Question. Kerala, with lower per capita income has a better human development ranking than Punjab. Hence, per capita income is not a useful criterion at all and should not be used to compare states. Do you agree? Discuss. [/question] [solution] Solution: Kerala, with lower per capita income has a better human development ranking than Punjab. However, it would be wrong to say that per capita income is not a useful criterion at all. Per capita income is certainly not the only criterion ...
Read More →Name two energy sources that you would consider to be renewable.
[question] Question. Name two energy sources that you would consider to be renewable. Give reasons for your choices. [/question] [solution] solution: (1) Water energy (hydro-energy), water on Earth can be used again and again to generate hydro energy as it is stored again and again in dams due to the water cycle that exists in nature. (2) Bio-mass energy, bio-mass can be managed by replacing the trees that have been cut down for fire-wood, cattle dung will be available as long as life exists on ...
Read More →An echo is returned in 3 s.
[question] Question. An echo is returned in $3 \mathrm{~s}$. What is the distance of the reflecting surface from the source, given that the speed of sound is $342 \mathrm{~ms}^{-1}$ ? [/question] [solution] Solution: Given, speed of sound, $\mathrm{v}=342 \mathrm{~m} \mathrm{~s}^{-1}$; time taken for hearing the echo, $\mathrm{t}=3 \mathrm{~s}$; distance of the reflecting surface, $\mathrm{s}=$ ? Now, $\mathrm{s}=\frac{\mathrm{v}}{2}=\frac{342}{2}=\mathbf{5 1 3} \mathbf{~ m}$ [/solution]...
Read More →Why do we use averages? Are there any limitations to their use? Illustrate with your own examples related to development.
[question] Question. Why do we use averages? Are there any limitations to their use? Illustrate with your own examples related to development. [/question] [solution] Solution: We use averages because they are useful for comparing differing quantities of the same category. For example, to compute the per capita income of a country, averages have to be used because there are differences in the incomes of diverse people. However, there are limitations to the use of averages. Even though they are us...
Read More →Hydrogen has been used as a rocket fuel.
[question] Question. Hydrogen has been used as a rocket fuel. Would you consider it a cleaner fuel than CNG ? Why or why not ? [/question] [solution] solution: Hydrogen is a cleaner fuel than CNG. This is because it produces water on burning whereas $\mathrm{CNG}$ on burning, produces $\mathrm{CO}_{2}, \mathrm{H}_{2} \mathrm{O}$ and $\mathrm{CO}$. [/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) Which one of the following places receives the highest rainfall in the world? (a) Silchar (c) Cherrapunji (b) Mawsynram (d) Guwahati (ii) The wind blowing in the Northern Plains in the summers is known as (a) Kaal Baisakhi (c) Trade Winds (b) Loo (d) None of the above (iii) Which one of the following causes rainfall during winters in north-western part of India? (a) Cyclonic depression (c) Western disturbanc...
Read More →In which of the three media, air, water or iron, does sound travel the fastest at a particular temperature?
[question] Question. In which of the three media, air, water or iron, does sound travel the fastest at a particular temperature? [/question] [solution] Solution: Sound travels the fastest in solids. Its speed decreases in liquids and it is the slowest in gases. Therefore, for a given temperature, sound travels fastest in iron. [/solution]...
Read More →Can any source of energy be pollution-free ?
[question] Question. Can any source of energy be pollution-free ? Why or why not ? [/question] [solution] solution: No source of energy is totally pollution-free, only the degree and the manner of pollution vary. For example, solar cells seem to be non-polluting but environmental pollution is caused in the manufacturing of solar cells. [/solution]...
Read More →What are the advantages of nuclear energy ?
[question] Question. What are the advantages of nuclear energy ? [/question] [solution] solution: (1) The mass of nuclear fuel like uranium-235 required is extremely small as compared to a fossil fuel to produce the same amount of energy. (2) In a nuclear power plant, the nuclear fuel supplies energy over a long period of time. [/solution]...
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