1. ‘Solar water still’ is a device to: 1. Produce potable water by using solar energy. 2. Pump water by using solar energy. 3. Generate electricity by using solar energy. 4. Produce heat using solar energy.
Answer 1 Explanation: Production of Still Water The amount of solar energy (insolation) and the ambient temperature are used to produce solar stills. Per sun-hour, a SolAqua solar still generates roughly 0.8 litres of cleaned water (i.e. 1 kWh). Distillation mimics the way rain falls in nature. Water is heated to the level of evaporation by the sun’s energy. Water vapour rises when the water evaporates, condensing back into water when it cools and collects. Impurities like salts and heavy metals are left behind, and microbiological organisms are removed. The end result is distilled drinking water that is 100% pure. Solar still can be made anywhere and is portable. ©navclasses
2. The only UN treaty related to environmental issues which has been ratified by all 197 UN member states is: 1. Montreal protocol 2. Kyoto protocol 3. Paris agreement 4. Basel convention
Answer 1 Explanation: The Montreal Protocol is a United Nations pact on environmental issues that has been adopted by all 197 UN member nations. ©navclasses
3. Statement I: Long stretches of major rivers of India have very low Biochemical Oxygen Demand (BOD) values. Statement II : In rivers oxygen is added into water by diffusion from air due to its turbulent and rapid flow. 1 Both Statement I and Statement II are correct. 2. Both Statement I and Statement II are incorrect. 3 Statement I is correct but Statement II is incorrect. 4 Statement I is incorrect but Statement II is correct.
Answer 4 Explanation: Statement I: Polluted river stretches are characterised as polluted areas in a continuous sequence on BOD concentrations that exceed a certain threshold. According to the water quality evaluation for identifying polluted river stretches, 31 states and union territories have rivers and streams that do not meet water quality guidelines. Maharashtra has the most contaminated river stretches, with 53 in total, followed by Assam, Madhya Pradesh, Kerala, Gujarat, Odisha, West Bengal, and Karnataka. Uttar Pradesh, Goa, Uttarakhand, Mizoram, Manipur, Jammu & Kashmir, Telangana, Meghalaya, Jharkhand, Himachal Pradesh, Tripura, Tamilnadu, Nagaland, Bihar, Chattisgarh, Andhra Pradesh, Sikkim, Punjab, Rajasthan, Puducherry, Haryana, and Delhi are among the states. Statement II: Diffusion from the surrounding air, aeration (rapid movement), and as a waste product of photosynthesis all contribute to the presence of oxygen in water. Temperature has a big impact on the amount of dissolved oxygen gas. Dissolved oxygen is similarly affected by atmospheric pressure. The amount of oxygen (or any other gas) that may dissolve in pure water (the saturation point) is inversely related to the water’s temperature. The less dissolved oxygen in the water, the warmer it is. Dissolved oxygen is affected by the structure of a stream or river. Higher oxygen is absorbed into the water when a stream or river has more turbulence, such as waterfalls or rapids. Furthermore, wind-induced turbulence on the surface of a body of water tends to raise dissolved oxygen levels. ©navclasses
4. The underlying purpose of environmental education is to: A. Adjust to environmental challenges. B. Help face environmental hazards. C. Promote an individual’s critical-thinking about emerging issues. D. Increase public awareness and knowledge of environmental issues. E. Enhance problem-solving and decision-making skills in respect of handling environmental issues. Choose the correct answer from the options given below: 1 (A), (B). (C) only. 2 (C), (D), (E) only. 3 (B). (C), (D) only. 4 (D), (E), (A) only.
Answer 2 Explanation: Adjusting to environmental challenges and helping face environmental hazards are environmental strategies to cope with adverse effects. > Environmental education is to get knowledge about through awareness, to be able to think critically about issues, by Improving problem-solving and decision-making abilities when dealing with environmental challenges. ©navclasses
5. As of now, which of the following is a leading country in wind energy based electricity generation? A. India B. France C. China D. Denmark
Answer 3 Explanation: Installed capacities of wind energy (as of March 2021): > China – 288.32 GW > United States – 122.32 GW > Germany – 62.85 GW > India – 38.63 GW > Spain – 27.24 GW. ©navclasses
6. Identify the primary air pollutant among the following: (1) Ozone. (2) Black carbon aerosols. (3) Sulphate aerosols. (4) Peroxyacetyl Nitrate (PAN).
Answer 2 Explanation: Black carbon (BC) aerosol, also known as soot, is the most common form of light-absorbing particulate matter in the atmosphere. > Black carbon emissions are mostly created by man activities, like heating & transportation, when fossil fuels, biofuels, and biomass are burned inefficiently. ©navclasses
7. In PhotoVoltaic system (PV-system) arrange the following from smallest to the largest unit A. S Module B. Array C. Solar cell D. Array field (1) (B), (D), (A), (C) (2) (B), (D), (C). (A) (3) (C), (B), (D), (A) (4) (C), (A), (B), (D)
Answer 4 Explanation: Sequences in photovoltaic systems (PV-system) are solar cell, solar module, solar panel, solar array, array field. ©navclasses
8. Match List I with List II. (Toxic and Hazardous substances) (Major sources) (A) Vinyl chloride (I) Electric Insulations (B) Polychlorinated biphenyls (PCBs) (II) Fuel combustion (C) Benzo(a)pyrene (III) Plastics Industrial uses (D) Polycyclic Aromatic Hydrocarbons (IV) Waste Incineration 1 (A)-(I), (B)-(III), (C)-(IV), (D)-(II) 2 (A)-(I), (B)-(III), (C)-(II), (D)-(IV) 3 (A)-(III). (B)-(IV). (C)-(II), (D)-(I) 4 (A)-(III). (B)-(I), (C)-(IV), (D)-(II)
Answer 4 Explanation: Vinyl chloride is a chlorinated hydrocarbon that exists as a colourless, extremely flammable gas with a faint, sweet odour. When heated to breakdown, it can generate poisonous gases such as carbon dioxide, carbon monoxide, hydrogen chloride, and phosgene. Vinyl chloride is largely utilised in the production of polyvinyl chloride, which is used to make plastics. This chemical damages the central and peripheral neurological systems, as well as the liver. Polychlorinated Biphenyls (PCBs) are a type of polychlorinated biphenyl (PCBs). PCBs are a class of organic compounds created by humans that contain carbon, hydrogen, and chlorine atoms. PCBs are odourless and tasteless, with a viscosity that ranges from an oil to a waxy solid. > Electrical, heat transfer, and hydraulic equipment. > Plasticizers in paints, plastics, and rubber products. > Pigments, dyes, and carbonless copy paper. > Other industrial applications PCBs were employed in hundreds of industrial and commercial applications, including: In humans, benzo[a]pyrene would be a cancer-causing substance. Benzo[a]pyrene is a polycyclic aromatic hydrocarbon created by incomplete combustion of organic matter at temperatures ranging from 300 °C (572 °F) to 600 °C (1,112 °F). In people and animals, there is some proof that it affects skin, lung, & bladder cancer. The danger of skin cancer is increased if benzo(a)pyrene is present on the skin when it is exposed to sunshine or ultraviolet light. Polycyclic aromatic hydrocarbons (PAHs) are a type of polycyclic aromatic PAHs are a collection of compounds found in coal, crude oil, and petrol in their natural state. PAHs can also be found in coal-tar pitch, creosote, and asphalt, which are all generated from fossil fuels. PAHs can be emitted when coal is converted to natural gas. ©navclasses
9. Match List I with List II. (International Agreements) (Provisions) (A) Montreal Protocol (I) Clean affordable energy (B) Kyoto Protocol (II) Controlling consumption and production of Halons (C) Convention on Biodiversity (III) Emissions trading (D) International Solar Alliance (IV) Clearing House Mechanism Choose the correct answer from the options given below: 1. (A)-(IV), (B)-(II), (C)-(III), (D)-(I) 2. (A)-(II). (B)-(I), (C)-(III), (D)-(V) 3. (A)-(II), (B)-(I), (C)-(IV), (D)-(III) 4. (A)-(II), (B)-(III), (C)-(IV), (D)-(I)
Answer 4 Explanation: (A) Montreal Protocol is to reduce ozone depletion by Controlling consumption and production of Halons. (B) Kyoto Protocol has the option of Emissions trading under polluter pay principle. (C) Convention on Biodiversity has Clearing House Mechanism. > The Convention on Biological Diversity’s Clearing-House System (CHM) was formed in response to Article 18.3 of the Convention. > The central clearing-house mechanism delivers effective global information services to help implement the Development Plan for Biodiversity 2011-2020. National clearing-house systems provide useful information to help with the implementation of national biodiversity strategy and action plan. The clearing-house mechanism’s network and services are greatly expanded thanks to the collaboration of partners. (D) International Solar Alliance is to use solar energy Clean affordable energy. ©navclasses
10. Exposure to excessive noise pollution can cause: A. Hearing impairment. B. Insomnia. C. Rise in blood pressure. D. Respiratory disease. E. Reduced work efficiency. (1) (A), (C), (E) only (2) (A), (C), (D) only (3) (B), (C) &(E) only (4) (A). (B), (C) & (E) only
Answer 4 Explanation: Exposure to excessive noise pollution can cause: > Hearing impairment. > Insomnia – sleep disorder. > Rise in blood pressure due to noise, stress. > Reduced work efficiency as Noise has an impact on the cardiovascular system of workers, causing hypertension, headaches, weariness, uneasiness, and hostility. Respiratory diseases are caused by breathing problems or air pollution. ©navclasses