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Chapter —5, Water, , Exercise, , 1., (A) What is precipitation?, , Answer:, , The water from the water sources on the surface of the earth evaporates, and rise high up in the sky. As they reach height, they start cooling, down and convert to tiny droplets of water. These water droplets join, together to form heavy and dense clouds. When the clouds become, heavy and cannot hold more water, the droplets fall on the earth in, different forms such as rain, hail, frost, fog, sleet or snow. This process, of falling down of water in different forms from the surface of the earth, is called precipitation., , , , , , , Run off, , Evaporation, , _, , (B) What is water cycle?, , Answer:
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The water in the nature changes its form from one form to the other and, circulates in the nature continuously. The continuous movement of, water where, the water continually changes its form and circulates, between oceans, atmosphere and land is known as the water cycle., , (C) What are the factors affecting the height of the waves?, Answer:, , During high winds, the high tides arise in the seas and oceans. Due to, sudden movement of the lithospheric plates, earthquake, volcanoes and, underwater landslides occur. As result of these sudden movements,, large amount of water shift and causes an increase in the height of the, waves., , (D) Which factors affect the movement of ocean water?, Answer:, , There can be a number of reasons that affect the movement of ocean, water. Temperature, winds, gravitational pull of the moon, and warm, and cold currents are some factors that affect the movement of ocean, water., , (E) What are tides and how are they caused?, Answer:, , The rhythmic rise and fall of ocean water twice in a day are called tide., The strong gravitational pull exerted by the sun and the moon on the, earth’s surface cause the tides. The gravitational attraction of the moon, causes the oceans to bulge out in the direction of the moon. The rise, and fall of water due to tides is used to generate electricity in some, places.
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(F) What are ocean currents?, Answer:, , Ocean currents are streams of water flowing constantly on the ocean, surface in definite directions. The ocean currents may be warm or cold., , 2., (A) Give reasons., Ocean water is salty?, , Answer:, , The ocean water is salty as it contains different salts and minerals in it., The presence of high concentration of these salts make the water, extremely salty and unfit for drinking., , (B) Give reasons., The quality of water is deteriorating?, , Answer:, , Water is a necessary thing that we need to survive. There are a number, of reason due to which the quality of water is getting deteriorated., , 1. Throwing garbage and other waste in the nearby water bodies., 2. Discharge of chemicals and other industrial waste in the water bodies, , 3. Flow of water from the fields and farms that contain harmful, fertilizers, pesticides and insecticides., , 4. Bathing of animals and washing clothes in water., , 3., , (A) Tick the correct answer:, The process by which water continually changes its form and, circulates between oceans, atmosphere and land.
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(a) Water cycle, (b) Tides, (c) Ocean currents, , Answer:, , The process by which water continually changes its form and circulates, between oceans, atmosphere and land is known as the water cycle., , (B) Tick the correct answer:, Generally, the warm ocean currents originate near, (a) Poles, (b) Equator, (c) None of these, , Answer:, , The warm ocean currents originate near the equator and move towards, the poles. The cold currents carry water from polar or higher latitudes, to tropical or lower latitudes., , (C)_ Tick the correct answer:, The rhythmic rise and fall of ocean water twice a day is called, (a) Tide, (b) Ocean currents, (c) Weave, , Answer:, , The rhythmic rise and fall of ocean water twice in a day is called a tide., The strong gravitational pull exerted by the sun and the moon on the, earth’s surface causes the tides., , 4. Match the following:, , , , , , , , , , (i) Caspian Sea (a) Largest lake
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(ii) Tide (b) Periodic rise and fall of water, , , , (iii) Tsunami (c) Strong seismic waves, , , , (iv) Ocean currents (d) Streams of water moving along, definite paths, , , , (e) Water cycle, , , , , , , , , , Answer:, , 1. Caspian Sea (a) Largest lake, , Caspian Sea is the largest lake. It is also known as full-fledged sea., , 2. Tide (b) Periodic rise and fall of water, , The rhythmic rise and fall of ocean water twice in a day is called a tide, 3. Tsunami (c) strong seismic waves, , An earthquake, a volcanic eruption or underwater landslides can shift, large amounts of ocean water. As a result, a huge tidal wave called, tsunami, is formed., , 4. Ocean currents (d) streams of water in definite paths, , Ocean currents are streams of water flowing constantly on the ocean, surface in definite directions., , 5. For fun, Be a detective, (i) The name of one river is hidden in each of the sentences below., Spot it.
