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Plateau is characterized by horizontally layered lava. 

Arabian sea islands are located 200 to 440 km off the south western coast of India. 

India spreads from Himalaya in the north to Kanyakumari in the south.

Pakistan is present at the north west of India.

Credit Rating for different states, namely. Maharashtra, Tamil Nadu, Madhya Pradesh, Andhra Pradesh and Kerala is done by CRISIL.

Afghanistan is the nation which shares the least boundary with India.

Jammu and Kashmir state of India shares its land boundary with Afghanistan.

Kanyakumari is the southern most part of Indian mainland.

Kanyakumari is the southernmost tip of the Indian peninsula.

India shares its maritime boundaries with Pakistan, Sri Lanka, Maldives, Indonesia, Bangladesh and Myanmar.

The distance between northernmost point in Kashmir to the southernmost mainland point i.e. Kanyakumari is about 3,214 kilometres.

(1) The fuel used in the thermal power plant is coal. Coal contains chemical energy. Upon burning it releases heat energy. This heat is used for generation of electricity in the thermal power plants. 

(2) Problems associated with power 8enerations by thermal power plant: 

(a) Air pollution: Due to burning of coal, there is emission of carbon dioxide, carbon monoxide, sulphur dioxide and nitrogen dioxide gases. These are harmful and toxic to health. 

(b) Soot particles emitted during combustion can cause severe respiratory problems such as asthma.

In the year 1960 at Pant Nagar in Uttar Pradesh.

Correct option is (c) September

 Laboratory preparation of nitric acid.

All glass apparatus is used in the laboratory preparation of nitric acid. 

1. Cone, sulphuric acid 

2. Glass retort 

3. Precautions are: 

• Use all glass apparatus with no wooden or rubber cork. 
• Control the temperature carefully at nearly 200 °C. 

4. Concentrated nitric acid vapours – condense and are collected in the water-cooled receiver. 

5. The vapours obtained in the receiver on heating alone or with copper turnings evolve – reddish brown fumes of nitrogen dioxide which turns acidified ferrous sulphate solution brown – proving that the vapours are of nitric acid. 

Nitric acid is highly corrossive and a strong oxidising agent. It attacks rubber and wooden corks. Therefore, all glass apparatus should be used for the preparation of nitric acid in the laboratory.

S + 6HNO₃ (conc.) → H₂SO₄ + 2H₂O + 6NO₂ (g).

(a) 1eq. mass of the substance requires 96500 coulombs

Since the element is monoatomic, thus eq. mass = mol. Mass

6.023 × 10²³ atoms require 96500C

1 atoms require (96500/6.023) x 10²³C = 1.6 x 10^-19C

(b) Since the element is diatomic eq.mass = (1/2) mol.mass

∴ (1/2) × 6.023 × 10²³ atoms 2eq. 96500 C

=> 1 atom require = (96500 x 2)/6.023 x 10²³ = 3.2 x 10^-19C

Crowding: It is psychological crampedness. It manifests following features: 

(a) Feeling of discomfort because of too many people or things around us the experience of physical restriction and sometimes the lack of privacy. 

(b) Crowding is the person’s reaction to the presence of a large number of persons within a particular area or space. 

Features of Crowding; Crowding has the following features: 

— Crowding gives feeling of discomfort. 

— It gives a feeling that individual privacy is being threatened. 

— It gives feeling that individual’s personal space is being invaded. 

— It gives negative view of a space around the person. 

— Crowding develops feelings of loss of control over social interaction. Crowding is studied by various psychologists in India and abroad. Crowding is not always experienced in high density setting nor all people experience its negative effects. For example, Mela has high density but still people enjoy it. 

Effects of Crowding and High Density: (а) Crowding and High density may lead to abnormal behaviour and aggression. e.g., an increase in population has sometimes been found to be accompanied by an increase in violent crime.

 (b) Crowding leads to lowered performance on difficult tasks that involve cognitive processes and has adverse effects on memory and the emotional state. 

(c) Children growing up in very crowded households show lower academic performance. They also show a weaker tendency to continue working on a task if they are unsuccessful at it, compared to children growing up in non-crowded households. They experience greater conflicts with parents and get less support from their family members. 

(d) The nature of social interaction determines the degree to which an individual will react to crowding. For example, in parties, large number of persons may not cause stress rather it may lead to positive emotional reactions. 

(e) Individuals differ in the degree to which they show negative effects of crowding and also in the nature of these reactions. 

Two kinds of tolerance can be mentioned that may explain these individual differences: (i) Crowding Tolerance (ii) Competition Tolerance

 (i) Crowding Tolerance; It refers to the ability of a person to mentally deal with the high density or crowding environment, e.g., crowded residence. •It is developed because people can use to manage people around them. •It is modifying ones perception one holds regarding high density/crowded situations. •Indians in general have more crowding tolerance. 

(ii) Competition Tolerance: It is the ability to put up with a situation in which individuals would have to compete with many others for even basic resources including physical space. Since there is a greater possibility of competition for resources in a crowded setting, the reaction to that setting would be influenced by the extent of tolerance for competition for resources. 

(iii) Cultural Characteristics: It may determine the extent to which a particular environment is judged to be subjectively more crowded or less crowded.

Noise is defined as an unwanted sound or sounds that create an effective response. Some may not be disturbed by even a loud-speaker sound, on the other hand, some might even find whistle, tinkling of wind as noise. Thus, any sound “which an individual finds unwanted is noise.” 

Noise (sound pollution) leads to adverse psychological effects. 

How the noise affect the individual depends on: 

(a) its intensity (loudness), loud sound is often unpleasant and irritating. 

(b) predictability, we can adapt more easily to a regular, predictable sound such as ‘ chirping of birds in the morning. 

(c) Perceived Control: The negative effects of noise are reduced when individuals perceive that they have control over it. 

Effects of noise (sound-pollution) on task performance:

(i) When the task being performed is a simple mental task, such as addition of numbers, noise does not affect overall performance whether it is loud or soft. 

(ii) If the task being performed is very interesting, then, too, the presence of noise does not affect performance. 

(iii) When the noise comes at intervals and in an unpredictable way, it is experienced as more disturbing than the noise being continuously present. 

(iv) Difficult task performance requires full concentration, then intense, unpredictable and uncontrollable noise reduces the level of task performance. ‘ 

(iv) When switching off the noise is within the control of the person, the numbers of ’ errors in task performance decrease.

Environment significantly influences various physical and psychological aspects of human behaviour. 

Some are as follows: 

(a) Environmental Influence on Perception: According to researches, our perception is influenced by the environment in which we live. For example. Tribal societies of Africa living in Circular huts show less error in a geometric illusion (the Muller Lyer illusion) than people from cities, living in houses with angular walls. 

(b) Environmental Influence on Emotions: For example, watching quietly flowing river, a smiling flowers or a tranquil mountain top provides joy and happiness. 

• Natural disasters, landslides can provide deep depression and sorrow, lack of control over their lives. 

• Such an influence is traumatic, changes people’s lives forever, and can last for a long time after the actual event in the form of post-traumatic stress disorder. 

(c) Ecological Influence on Occupation, Living style and Attitudes: 

(i) The natural environment of a particular region determines the people living in that region will develop what type of societies—may be agricultural or may be industrial. 

(ii) In turn, the occupation determines the life-style and attitudes of the residents of a particular geographical region. 

Human behaviour particularly influencing on the environment in negative manner. Following are the environmental stressors which effect human beings, although many are created by human beings themselves. 

1. Pollution: 

(a) Air-pollution: Emission of toxic gases due to automobile and industrial emissions cause adverse effect on the health. 

- Air-pollution reduces visibility and leads to eye irritation, headache, fatigue, occurrence of cancer of respiratory system. 

(b) Noise or sound pollution: Any sound which an individual finds unpleasant in a particular situation is considered noise or sound-pollution. Noise (sound pollution) leads to adverse psychological effects. It may leads to high level of stress, narrowing of attention, decrease in concentration, etc. 

(c) Water-pollution: Various problems related to digestive system and gastrointestinal issues occur due to water-pollution.

2. Noise 

Any unpleasant, irritating or interfering sound is called as Noise. 

– Noise is an environmental stressor which may affect adversely depending on (a) Predictability (b) Controllability (c) Intensity 

3. Crowding and Density: 

• Crowding is the subjective feeling of crampedness or being too close to each other. It has negative effects on task performance, personality, interpersonal relationship, general physical and mental health. 

• Density is an objective geographical term which refers to number of persons living within the available space, or per square meter area. 

4. Natural and Man-made Disasters: Natural disasters are earthquake, volcanic eruption, windstorm, tornado, cyclone, famine etc. 

— There are man-made disasters also; like Bhopal gas tragedy and nuclear bomb explosion in Japan, which not only caused extensive damage to property and physical environment but also had long-term effects on the lives of people. 

— Man is largely responsible for regarding the quality of environment that surrounds us. Almost everything humans do has small but cumulative effects on the environment in which we live. e.g., driving a car, using a hair spray, use of refrigerator, etc.

Correct option is (d) Contingency

Correct option is (a) Traditional

Correct option  (C) Glass sheet 

Explanation:

The solar cooker box is covered with a glass sheet that traps more and more Sun's heat rays in the solar cooker by producing green-house effect.

Given: 

50 VSD = 49 MSD

(VSD-Vernier Scale division, MSD-Main scale divisions)

⇒ 1 MSD = \(\frac{50}{49}VSD\)

1 VSD = \(\frac{49}{50}MSD\)

Inaccuracy (minimum) = \(\frac{1}{50}\times0.5mm\)

=0.01 mm

The trapping of heat in the environment due to the presence of greenhouse gases like CO₂, methane, water vapour etc is the greenhouse effect. This raises the temperature of the earth.
In the solar cooker the same process occurs, the sun rays are reflected by the mirror are trapped in the solar cooker by the glass plate (green house effect) and is used to heat the food.

(B) It is made from semiconductor material.

The answer is (b) larger amount of potential energy is converted into kinetic energy

Solar Cookers and solar water heaters

• A black surface absorbs more heat as compared to a white or a reflecting surface under identical conditions. 
• Solar cookers and solar water heaters use this property in their working. 
• Some solar cookers achieve a higher temperature by using mirrors to focus the rays of the Sun. 
• Solar cookers are covered with a glass plate. 
• Solar energy trapped is reflected by the glass sheet which make the food cook. 

Solar Cell 

• A typical cell develops a voltage of 0.5–1 V and can produce about 0.7 W of electricity when exposed to the Sun. 
• A large number of solar cells are, combined in an arrangement called solar cell panel that can deliver enough electricity for practical use.
• The principal advantages associated with solar cells are that they have no moving parts, require little maintenance and work quite satisfactorily without the use of any focussing device. 
• Another advantage is that they can be set up in remote and inaccessible hamlets or very sparsely inhabited areas in which laying of a power transmission line may be expensive and not commercially viable.

1. b. Renewable

2. b. Non-conventional

3. a. Non-conventional

4. b. Renewable

5. c. Nuclear energy

The answer is (a) Sun can be taken as an inexhaustible source of energy

• Fossil fuel is an exhaustible source. 
• Hydro and wind energy plants can have large environmental impacts by changing the environment and affecting land use, homes, and natural habitats in the dam area. 
• Disposing off waste from a nuclear power plant is the major issue faced by nuclear plant.

The difference in temperature between warm surface, water heated by the sun and colder water found at ocean depth is a source of energy called Ocean thermal energy. The difference in temperature is exploited in OTE conversion plants. The warm surface water is used to boil to volatile liquid like ammonia. The vapours are used to run the turbine of a generator.

Limitations :

(i) Efficient commercial exploitation is difficult.

(ii) Expensive set up.

The answer is (b) temperature difference at different levels in the ocean

Energy from surface is used to boil volatile liquid. Vapors from these are utilized to turn the turbine

Solar energy: a renewable source of energy, the energy produced through nuclear fusion 

Wind energy: wind is also a renewable source of energy, energy can also be backed up in storage cells 

Energy from sea, tidal and wave energy.

 It is not possible to make use of solar cells to meet all our energy needs because: 

(i) of limited availability of special grade semiconducting materials such as silicon and germanium. 

(ii)solar cells have lower efficiency as they depend entirely on intensity of solar radiation. 

(iii) the process of manufacturing of solar cells is very expensive, silver used for interconnection of cells in the panel further adds to the cost. 

Uses of solar cells: 

(i) They provide electric power to satellites and space probes. 

(ii) They provide electric power to off-shore drilling platforms and light houses. 

(iii) TV relay stations or wireless transmission systems located in remote areas use solar panels to get electric power.

Silicon, Germanium' (Any one) 

(Each solar cell produces a voltage of 0.5 volt.)

(i) Availability of special grades silicon used for making solar cells is limited.

(ii) Silver is used for the interconnection of the cells in the panel which adds to its cost.

(iii) Low efficiency of solar cells is another reason.

(i) In the solar cells, the energy is obtained only during the day, when the Sun shines.
(ii) In the solar cells, the solar- panel convert solar energy into electricity, which is stored in storage battery. The storage battery give the direct current but all the appliances are working by the alternating current, so first of all direct current is converted into alternating current by any suitable appliances before it can be used to run various devices. So, it increases the cost of using solar panels as the source of energy.
So, the solar cell is not used to meet all our energy needs.

When there is no change of position of an object with respect to time and if it remains stationary it is called rest.

20°C or 293 K in trapping geothermal energy.

It is not possible to make use of solar cells to meet all our energy needs because 

Silicon which is used to make solar cells is abundant in nature, but availability of special grade silicon for making the solar cells is limited. 

The entire process of manufacture is expensive, silver used for interconnection of solar cells in the panel adds to the cost. 

Domestic use is limited due to high costs

Uses of solar cells: 

•Artificial satellites and space probes like Mars orbiter use solar cells as their main source of energy. 

•Radio or wireless transmission systems or TV relay stations in remote locations use solar cell panels. 

•Traffic signals, calculators and many toys are fitted with solar cells

 Germanium, Silicon. 

Robots can perform mechanical and repetitive jobs faster, more accurately than human beings. It can also handle dangerous materials and explore distant planets.

(d) Nanobots

Electronic sensors are a robot’s eyes and ears. These are the important parts.

Nanobots are robots scaled down to microscopic size in order to put them into very small places to perform a function.