Answer:
1. Answer: (b) 22nd March
Explanation: World Water Day is an annual United Nations (UN) observance day held on 22 March that highlights the importance of fresh water. The day is used to advocate for the sustainable management of freshwater resources.
2. Answer: (a) 2003
Explanation: Year 2003 was observed as the International Year of Freshwater to make people aware of this dwindling natural resource.
3. Answer: (d) A family gets three buckets of water per person per day
Explanation: Water shortage is the lack of sufficient available water resources to meet the demands of water usage within a region.There seems no water shortage as three buckets of water per person is enough for satisfying their daily needs.
4. Answer: (a) 0.006%
Explanation:The total amount of fresh water available for use is about 0.006% of the total water present on earth as about 97.4% of the total water on earth is in seas and ocean and 2% water is present in the form of glaciers and in polar ice caps.
5. Answer: (c) Drip irrigation
Explanation: One such traditional practice listed above is construction of bawris which is actually constructing deep wells followed by steps made by mud deep in the ground. These bawris would get filled with water whenever there is rain and hence was used by villagers to carry out their daily chores and to collect water.
6. Answer: (d) 50 litres
Explanation: The amount of water recommended by the United Nations for drinking, washing, cooking and maintaining proper hygiene is a minimum of 50 litres per person per day. This amount is about two and a half buckets of water per person per day.
7. Answer: (c) importance of water
Explanation: Every drop counts' is the slogan related to the importance of water. Water is very important for humans as well as for animals. But fresh water is less than one percent of water available on the Earth.
8. Answer: (d) Rainwater harvesting
Explanation: Liquid water evaporates into water vapor, condenses to form clouds, and precipitates back to earth in the form of rain and snow. The water cycle does not involve rainwater harvesting as it is the collection and storage of rain, rather than allowing it to run off.
9. Answer: (a) A pukka floor
Explanation: A pukka floor is a cement floor which is impenetrable to water. Hence water cannot seep through the pukka floor.
10. Answer: (a) increasing industries
Explanation: Every industry requires water in its production process. As a number of industries increases, more water is drawn from the ground. All of this result in depletion of the water table.
11. Answer: (c) gas
Explanation: Steam is water in the gas phase. Steam that is saturated or superheated is invisible; however, "steam" often refers to wet steam, the visible mist or aerosol of water droplets formed as water vapour condenses.
12. Answer: (b) the solid form
Explanation: Water can be found in liquid form in oceans, rivers, lakes and rain; in solid form in ice and snow; and as a gas (water vapour) in the atmosphere.
13. Answer: (b) lithosphere
Explanation:The outermost layer, called the crust, is solid, too. Together, these solid parts are called the lithosphere. Earth's crust is made up of hard rocks.
14. Answer: (c) Drip irrigation
Explanation: Drip irrigation is the method to use water economically. As in drip irrigation system the water is supplied drop by drop to plants which does not cause the wastage of water and supply as per the needs of the plants.
15. Answer: (b) Aquifer
Explanation: An aquifer is an underground layer of water-bearing permeable rock, rock fractures or unconsolidated materials (gravel, sand or salt). Ground water can be extracted using a water well.
16. Answer: (c) Addition of untreated sewage
Explanation: Essentially, the release of poorly treated or even completely untreated sewage is responsible for the frothing and foaming of the river water. Surfactants and phosphates that originate from detergents used in households and industrial laundries, when released in the river untreated, create the foam.
17. Answer: (a) bawaris
Explanation: Bawri were deep step wells built into the ground. It was the traditional way of rainwater harvesting.
18. Answer: (d) Water vapour
Explanation: Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere. Transpiration is essentially evaporation of water from plant leaves.
19. Answer: (a) rain
Explanation: The main source of water is the rainwater. The water cycle is a process that involves evaporation, condensation and precipitation and the output is rainwater. The water source is important in the water cycle.
20. Answer: (a) groundwater
Explanation: Groundwater, water that occurs below the surface of Earth, where it occupies all or part of the void spaces in soils or geologic strata. It is also called subsurface water to distinguish it from surface water, which is found in large bodies like the oceans or lakes or which flows overland in streams.
21. Answer: (d) Water
Explanation: The Earth has been blue for over 4 billion years because of the liquid water on its surface. There is only one known planet with permanent bodies of liquid water at its surface: ours. Earth sciences allow us to explain why the Earth has almost always been blue: it's neither too warm nor too cold.
22. Answer: (a) Infiltration
Explanation: Process of seeping of water into the ground is called infiltration . Infiltration is the process by which bulk of rainwater and melted snow soaks into subsurface soils and moves into rocks through cracks and pores,
23. Answer: (a) Kill germs
Explanation: Water chlorination is the process of adding chlorine or chlorine compounds such as sodium hypochlorite to water. This method is used to kill bacteria, viruses and other microbes in water. In particular, chlorination is used to prevent the spread of waterborne diseases such as cholera, dysentery, and typhoid.
24. Answer: (d) Water pollution
Explanation: The addition of any substance to water, which leads to change in its physical and chemical characteristic, is defined as water pollution.
25. Answer: (b) Condensation
Explanation: The process of changing water vapour into water is called condensation.This is due to the change of gaseous state of water into liquid state. Some common examples of condensation are Formation of drops of water on the outside of a glass of ice water. ,Formation of dew on grass overnight.
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