{"id":118785,"date":"2022-04-28T16:09:48","date_gmt":"2022-04-28T10:39:48","guid":{"rendered":"https:\/\/www.mapsofindia.com\/my-india\/?p=118785"},"modified":"2022-04-28T16:09:48","modified_gmt":"2022-04-28T10:39:48","slug":"chapter-14-movements-of-ocean-water-questions-and-answers-ncert-solutions-for-class-11-geographyfundamentals-of-physical-geography","status":"publish","type":"post","link":"https:\/\/www.mapsofindia.com\/my-india\/education\/chapter-14-movements-of-ocean-water-questions-and-answers-ncert-solutions-for-class-11-geographyfundamentals-of-physical-geography","title":{"rendered":"Chapter 14 – Movements of Ocean Water Questions and Answers: NCERT Solutions for Class 11 Geography(Fundamentals of Physical Geography)"},"content":{"rendered":"

1. Multiple choice questions.<\/h3>\n

Question 1(i).
\nUpward and downward movement of ocean water is known as the:
\n(a) Tide
\n(b) Current
\n(c) Wave
\n(d) None of the above.<\/h2>\n

Answer:
\n(a) Tide<\/h3>\n

Question 1(ii).
\nSpring tides are caused:
\n(a) As result of the moon and the sun pulling the earth gravitationally in the same direction.
\n(b) As result of the moon and the sun pulling the earth gravitationally in the opposite direction.
\n(c) Indention in the coast line.
\n(d) None of the above.<\/h2>\n

Answer:
\n(a) As result of the moon and the sun pulling the earth gravitationally in the same direction.<\/h3>\n

Question 1(iii).
\nThe distance between the earth and the moon is minimum when the moon is in:
\n(a) Aphelion
\n(b) Perigee
\n(c) Perihelion
\n(d) Apogee.<\/h2>\n

Answer:
\n(b) Perigee<\/h3>\n

Question 1(iv).
\nThe earth reaches its perihelion in:
\n(a) October
\n(b) September
\n(c) July
\n(d) January.<\/h2>\n

Answer:
\n(d) January<\/h3>\n

2. Answer the following questions in about 30 words.
\nQuestion 2(i).
\nWhat are waves?<\/h2>\n

Answer:
\nWaves are oscillatory movements in water, manifested by an alternate rise and fall of the sea surface. In other words, waves are actually the energy, not the water as such, which moves across the ocean surface. Water particles only travel in a small circle as a wave passes. The maximum wave height is determined by the strength of the wind, i.e. how long it blows and the area over which it blows in a single direction. Waves travel because wind pushes the water body in its course while gravity pulls the crests of the waves downward. The falling water pushes the former troughs upward, and the wave moves to a new position. The actual motion of the water beneath the waves is circular. It indicates that things are earned up and forward as the wave approaches, and down and back as it passes.<\/h3>\n

Question 2(ii).
\nWhere do waves in the ocean get their energy from?<\/h2>\n

Answer:
\nWind provides energy to the waves. Wind causes waves to travel in the ocean and the energy is released on shorelines. The motion of the surface water seldom affects the stagnant deep bottom water of the oceans. As a wave approaches the beach, it slows down. This is due to the friction occurring between the dynamic water and the seafloor. Waves continue to grow larger as they move and absorb energy from the wind. Most of the waves are caused by the wind driving against water. When a breeze of two knots or less blows over calm water, small ripples form and grow as the wind speed increases until white caps appear in the breaking waves.<\/h3>\n

Question 2(iii).
\nWhat are tides?<\/h2>\n

Answer:
\nThe periodical rise and fall of the sea level, once or twice a day, mainly due to the attraction of the sun and the moon, is called a tide. Tides vary in their frequency, direction and movement from place to place and also from time to time.<\/h3>\n

Question 2(iv).
\nHow are tides caused?<\/h2>\n

Answer:
\nTides are caused by:
\nThe moon\u2019s gravitational pull to a great extent
\nThe sun\u2019s gravitational pull to some extent are the major causes for the occurrence of tides.
\nAnother factor is centrifugal force, which is the force that acts to counter balance the gravity.
\nTogether, the gravitational pull and the centrifugal force are responsible for creating the two major tidal bulges on the earth. On the side of the earth facing the moon, a tidal bulge occurs while on the opposite side though the gravitational attraction of the moon is less as it is farther away, the centrifugal force causes tidal bulge on the other side. The \u2018tide-generating\u2019 force is the difference between these two forces; i.e. the gravitational attraction of the moon and the centrifugal force.<\/h3>\n

Question 2(v).
\nHow are tides related to navigation?<\/h2>\n

Answer:
\nSince tides are caused by the earth- moon-sun positions which are known accurately, the tides can be predicted well in advance. This helps the navigators and fishermen plan their activities. Tidal flows are of great importance in navigation. Tidal heights are very important, especially harbours near rivers and within estuaries having shallow \u2018bars\u2019 at the entrance, which prevent ships and boats from entering into the harbour. Kolkata port on Hugli river is an example for it.<\/h3>\n

3. Answer the following questions in about 150 words.
\nQuestion 3(i).
\nHow do currents affect the temperature? How does it affect the temperature of coastal areas in the N. W. Europe?<\/h2>\n

Answer:
\nImpact of currents on temperature varies depending on whether currents are warm or cold.
\n1. Cold currents: Cold currents bring cold water into warm water areas. These currents are usually found on the west coast of the continents in the low and middle latitudes (true in both hemispheres) and on the east coast in the higher latitudes in the Northern Hemisphere.
\n2. Warm currents: Warm currents bring warm water into cold water areas and are usually observed on the east coast of continents in the low and middle latitudes (true in both hemispheres). In the northern hemisphere they are found on the west coasts of continents in high latitudes.
\nIn North West Europe, warm currents exist. They increase the temperature in coastal areas of N. W. Europe.<\/h3>\n

Question 2(ii).
\nWhat are the causes of currents?<\/h2>\n

Answer:
\nOcean currents are like river flow in oceans. They are caused by two types of forces namely:
\n1. Primary forces that initiate the movement of water;
\n2. Secondary forces that influence the currents to flow.
\nPrimary Forces: The primary forces that influence the currents are:
\nHeating by solar energy: Heating by solar energy causes the water to expand. That is why, near the equator the ocean water is about 8 cm higher in level than in the middle latitudes. This causes a very slight gradient and water tends to flow down the slope.
\nWind: Wind blowing on the surface of the ocean pushes the water to move. Friction between the wind and the water surface affects the movement of the water body in its course.
\nGravity: Gravity tends to pull the water down the pile and create gradient variation.
\nCoriolis force: The Coriolis force intervenes and causes the water to move to the right in the northern hemisphere and to the left in the southern hemisphere. These large accumulations of water and the flow around them are called Gyres. These produce large circular currents in all the ocean basins.<\/h3>\n

Multiple Choice Questions<\/h3>\n

Question 1.
\nWhich force intervenes and causes the water to move to the right in the northern hemisphere and to the left in the southern hemisphere?
\n(a) Farrell law
\n(b) The Coriolis force
\n(c) Gravitational force
\n(d) Effect of rotation of the earth.<\/h2>\n

Answer:
\n(b) The Coriolis force<\/h3>\n

Question 2.
\nPrimary force which affects the ocean currents:
\n(a) Heating by solar energy
\n(b) Wind
\n(c) Gravity
\n(d) All of these.<\/h2>\n

Answer:
\n(d) All of these<\/h3>\n

Question 3.
\nWhat is the time between the high tide and low tide, when the water level is falling, is called?
\n(a) Ebb
\n(b) Waves
\n(c) Currents
\n(d) Gyres.<\/h2>\n

Answer:
\n(a) Ebb<\/h3>\n

Question 4.
\nThe Coriolis force intervenes and causes the water to move to the right in the northern hemisphere and to the left in the southern hemisphere. These large accumulations of water and the flow around them are called what?
\n(a) Ebb
\n(b) Waves
\n(c) Currents
\n(d) Gyres.<\/h2>\n

Answer:
\n(d) Gyres<\/h3>\n

Question 5.
\nWhat per cent of ocean water is in the form of deep water currents?
\n(a) 50%
\n(b) 60%
\n(c) 80%
\n(d) 90%.<\/h2>\n

Answer:
\n(d) 90%<\/h3>\n

Question 6.
\nTo what depth exist the upper layer of ocean stream?
\n(a) 200 metres
\n(b) 300 metres
\n(c) 40 metres
\n(d) 500 metres.<\/h2>\n

Answer:
\n(d) 500 metres<\/h3>\n

Question 7.
\nWhat is the name given to movement of water due to metrological effects?
\n(a) Surges
\n(b) Tides
\n(c) Waves
\n(d) Currents.<\/h2>\n

Answer:
\n(a) Surges<\/h3>\n

Question 8.
\nWhat is the name given to time when the distance between the earth and the moon is minimum?
\n(a) Aphelion
\n(b) Perigee
\n(c) Perihelion
\n(d) Apogee.<\/h2>\n

Answer:
\n(6) Perigee<\/h3>\n

Question 9.
\nThe heights and lowest points of a wave are called_______and_________.
\n(\u0430) Crest and trough
\n(b) Trough and crest
\n(c) Edd and surge
\n(d) Surge and ebb.<\/h2>\n

Answer:
\n(a) Crest and trough<\/h3>\n

Question 10.
\nHow much time interval normally exist between neap tides and spring tides?
\n(a) 7 days
\n(b) 10 days
\n(c) Two weeks
\n(d) One month.<\/h2>\n

Answer:
\n(a) 7 days<\/h3>\n

Question 11.
\nWhat percent of ocean water is in the form of surface currents?
\n(a) 50%
\n(b) 40%
\n(c) 20%
\n(d) 10%.<\/h2>\n

Answer:
\n(d) 10%<\/h3>\n

Question 12.
\nIt is the horizontal distance between two successive crests.
\n(a) Wave speed
\n(b) Wave length
\n(c) Wave frequency
\n(d) Wave gap.<\/h2>\n

Answer:
\n(b) Wave length<\/h3>\n

Question 13.
\nWhere do highest tide occur in the world?
\n(a) Bay of Fundy in Nova Scotia, Canada
\n(b) Bay of Hudson in USA
\n(c) Bay of Bengal in India
\n(d) Arabian Sea.<\/h2>\n

Answer:
\n(a) Bay of Fundy in Nova Scotia, Canada.<\/h3>\n

Question 14.
\nWhat is the unit for measuring speed of waves?
\n(a) Km
\n(b) Knot
\n(c) Cm
\n(d) Millibars.<\/h2>\n

Answer:
\n(b) Knot<\/h3>\n

Question 15.
\nAt which place is being a 3 watt electric generating plant established in Sundarban in West Bengal?
\n(a) Durgaduani
\n(b) Haldia
\n(c) Ganga
\n(d) 24 pargana.<\/h2>\n

Answer:
\n(a) Durgaduani<\/h3>\n

Question 16.
\nWhich of the following is not a primary force which affects ocean currents?
\n(\u0430) Heating by solar energy
\n(b) Wind
\n(c) Gravity
\n(d) Debilitation.<\/h2>\n

Answer:
\n(d) Debilitation<\/h3>\n

Question 17.
\nThose tides whose length varies are called what?
\n(a) Spring tides
\n(b) Neap tides
\n(c) Mixed tides
\n(d) High tides.<\/h2>\n

Answer:
\n(d) Mixed tides<\/h3>\n

Very Short Answer Type Questions<\/h3>\n

Question 1.
\nWhich forces influence the movement of ocean water?<\/h2>\n

Answer:
\nThe external forces like of the sun, moon and the winds influence the movement of ocean water.<\/h3>\n

Question 2.
\nWhat types of movements take place in ocean water.<\/h2>\n

Answer:
\nThe horizontal and vertical motions are common in ocean water bodies. The horizontal motion refers to the ocean currents and waves. The vertical motion refers to tides.<\/h3>\n

Question 3.
\nExplain different types of vertical movement in the ocean water.<\/h2>\n

Answer:
\nThe vertical motion refers to the rise and fall of water in the oceans and seas. Due to attraction of the sun and the moon, the ocean water is raised up and falls down twice a day. The upwelling of cold water from subsurface and the sinking of surface water are also forms of vertical motion of ocean water.<\/h3>\n

Question 4.
\nHow are ripples formed?<\/h2>\n

Answer:
\nWhen a breeze of two knots or less blows over calm water, small ripples form and grow as the wind speed increases until white caps appear in the breaking waves.<\/h3>\n

Question 5.
\nHow do steep and steady waves form?<\/h2>\n

Answer:
\nSteep waves are fairly young ones and are probably formed by local wind. Slow and steady waves originate from far away places, possibly from another hemisphere.<\/h3>\n

Question 6.
\nWhat factors cause tides?<\/h2>\n

Answer:
\nThe moon\u2019s gravitational pull to a great extent and to a lesser extent the sun\u2019s gravitational pull, are the major causes for the occurrence of tides. Another factor is centrifugal force, which is the force that acts to counter balance the gravity. Together, the gravitational pull and the centrifugal force are responsible for creating the two major tidal bulges on the earth.<\/h3>\n

Question 7.
\nWhere does highest tide occur in the world?<\/h2>\n

Answer:
\nThe highest tides in the world occur in the Bay ofFundy in Nova Scotia, Canada.<\/h3>\n

Question 8.
\nWhat are Semi-diurnal tides?<\/h2>\n

Answer:
\nThe most common tidal pattern, featuring two high tides and two low tides each day. The successive high or low tides are approximately of the same height.<\/h3>\n

Question 9.
\nWhat are Diurnal tides?<\/h2>\n

Answer:
\nThere is only one high tide and one low tide during each day. The successive high and low tides are approximately of the same height.<\/h3>\n

Question 10.
\nWhat is a Mixed tide?<\/h2>\n

Answer:
\nTides having variations in height are known as mixed tides. These tides generally occur along the west coast of North America and on many islands of the Pacific Ocean.<\/h3>\n

Question 11.
\nWhat are Spring tides?<\/h2>\n

Answer:
\nThe position of both the sun and the moon in relation to the earth has direct bearing on tide height. When the sun, the moon and the earth are in a straight line, the height of the tide will be higher. These are called spring tides.<\/h3>\n

Question 12.
\nWhat are neap tides?<\/h2>\n

Answer:
\nWhen the sun and moon are at right angles to each other and the forces of the sun and moon tend to counteract one another. The moon\u2019s attraction, though more than twice as strong as the sun\u2019s, is diminished by the counteracting force of the sun\u2019s gravitational pull. These are called neap tides.<\/h3>\n

Question 13.
\nDefine ocean currents.<\/h2>\n

Answer:
\nOcean currents are the continuous flow of huge amount of water in a definite direction. Ocean currents are like river flow in oceans. They represent a regular volume of water in a definite path and direction.<\/h3>\n

Question 14.
\nHow are fishing and oceanic currents related?<\/h2>\n

Answer:
\nThe mixing of warm and cold currents help to replenish the oxygen and favour the growth of planktons, the primary food for fish population. The best fishing grounds of the world exist mainly in these mixing zones.<\/h3>\n

Short Answer Type Questions<\/h3>\n

Question 1.
\nHow do ocean currents affect the climate? Explain.<\/h2>\n

Answer:
\nEffects of currents influenced by temperature.
\nWarm currents makes the place warmer where as the cold currents makes the place colder. Example, Warm currents of Koroshio makes the southern Japan less cold in winter whereas the cold current of Koroshio makes the winter longer and severe in north Japan.
\nWinds passing over warm currents absorbs lot of moisture and cause heavy rainfall in coastal areas. On the other hand winds passing over long currents do not get any warm currents as such, they make the climate of coastal areas dry. This is the reason why hot deserts are located near the coastal areas from where the cold current passes.
\nThe places where cold current and warm current near the coastal areas are found in abundance are rich fishing ground. For example, Newfoundland, the east coast of North America where Labrador current and Gulf stream meet.<\/h3>\n

Question 2.
\nExplain different types of ocean currents.<\/h2>\n

Answer:
\nOn the basis of depth:
\nSurface currents constitute aboutlO percent of all the water in the ocean. These water are the upper 400 m of the ocean.
\nDeep water currents make up the other 90 percent of the ocean water.
\nDeep waters sink into the deep ocean basins at high latitudes, where the . temperatures- are cold enough to cause the density to increase.
\nOn the basis of temperature:
\nCold currents: Cold currents bring cold water into warm water areas. These currents are usually found on the west coast of the continents in the low and middle latitudes and on the east coast in the higher latitudes in the northern hemisphere;
\nWarm currents: Warm currents bring warm water into cold water areas and are usually observed on the east coast of continents in the low and middle latitudes. In the northern hemisphere they are found on the west coasts of continents in high latitudes.<\/h3>\n

Question 3.
\nHow do ocean currents get affected by winds and Coriolis force?<\/h2>\n

Answer:
\nWind: Wind blowing on the surface of the ocean pushes the water to move. Friction between the wind and the water surface affects the movement of the water body in its course.
\nThe Coriolis force: The coroilis intervenes and cause the water to move to the right in the northern hemisphere and to the left in the southern hemisphere.<\/h3>\n

Question 4.
\nDifferentiate between spring tides and neap tides.<\/h2>\n

Answer:
\nS.no.
\nSpring Tides
\nNeap Tides
\n1.
\nIt occurs twice each month new moon day because the sun, moon and earth are in the straight line.
\nThey occur at first and third quarter of the moon. Because during these days the sun, moon form a right angle with each other.
\n2.
\nWhen the rise and fall is more than the normal then it is called the spring tides.
\nThe rise and the fall is considerably low than the normal level.
\n3.
\nIt is due to complimentary gravitational effect and cause sun, moon and earth are in the same.
\nHere the tidal forces do not supplement each other because the moon and earth are in right angles and so the velocity of tidal current slows down.<\/h3>\n

Long Answer Type Questions<\/h3>\n

Question 1.
\nIn how many categories can tides be classified on the basis of their height and frequency?<\/h2>\n

Answer:
\nSemi-diurnal tide: It is the most common tidal pattern, featuring two high tides and two low tides each day. The successive high or low tides are approximately of the same height.
\nDiurnal tide: There is only one high tide and one low tide during each day. The successive high and low tides are approximately of the same height.
\nMixed tide: Tides having variations in height are known as mixed tides. These tides generally occur along the west coast of North America and on many islands of the Pacific Ocean.
\nSpring tides: The position of both the sun and the moon in relation to the earth has direct bearing on tide height. When the sun, the moon and the earth are in a straight line, the height of the tide will be higher. These are called spring tides.
\nNeap tides: Wlien the sun and moon are at right angles to each other and the forces of the sun and moon tend to counteract one another. The moon\u2019s attraction, though more than twice as strong as the sun\u2019s, is diminished by the counteracting force of the sun\u2019s gravitational pull. These are called neap tides.<\/h3>\n

Question 2.
\nWhite the characteristics of waves in the oceanic water.<\/h2>\n

Answer:
\nCharacteristics of waves in the oceanic water are given below:
\nThe highest and lowest points of a wave are called the crest and trough.
\nWave height is the vertical distance from the bottom of a trough to the top of a crest of a wave.
\nWave amplitude is one-half of the wave height.
\nWave period is merely the time interval between two successive wave crests.
\nWavelength is the horizontal distance between two successive crests.
\nWave speed is the rate at which the wave moves through the water, and is measured in knots.
\nWave frequency is the number of waves passing a given point during a one- second time interval.<\/h3>\n

Question 3.
\nExplain how do heating of solar energy, wind, gravitation and coriolis force affect the ocean currents.<\/h2>\n

Answer:
\nHeating by solar energy: Heating by solar energy causes the water to expand, that is why, near the equator the ocean water is about 8 cm higher in level than in the middle latitudes. This causes a very slight gradient and water tends to flow down the slope.
\nWind: Wind blowing on the surface of the ocean pushes the water to move. Friction between the wind and the water surface affects the movement of the water body in its course.
\nGravity: Gravity tends to pull the water down the pile and create gradient variation.
\nThe Coriolis force: The coriolis intervenes and cause the water to move to the right in the northern hemisphere and to the left in the southern hemisphere.<\/h3>\n

Question 4.
\nDifferentiate between warm currents and cold currents.<\/h2>\n

Answer:
\nS.no.
\nWarm currents
\nCold currents
\n1.
\nThey flow from equatorial regions to high latitudes.
\nThey flow from polar region to low latitudes.
\n2.
\nIts temperature is higher than the surrounding water.
\nIts temperature is below than the surrounding water.
\n3.
\nIt raises the temperature of coastal areas and are observed normally on the east coast of lower and middle latitude.
\nIt reduces the temperature of the coastal area and are observed on the west of continent in lower and middle latitudes.
\n4.
\nWinds passing over warm currents absorb a good amount of moisture and bring heavy rainfall on the coastal areas.
\nWinds passing over cold currents becomes dry and little rainfall on the coaarea.
\n5.
\nWarm currents are of great help to navigation because they melt ice bergs.
\nCold currents hinder navigation because they create ice bergs.
\n6.
\nWarm currents keep the ports open in the polar regions free from ice.
\nCold currents make the parts unoperational in lower latitudes as they are ice bound.<\/h3>\n","protected":false},"excerpt":{"rendered":"

Class 11 Geography(Fundamentals of Physical Geography) NCERT book solutions for Chapter 14 – Movements of Ocean Water Questions and Answers.<\/p>\n","protected":false},"author":21830,"featured_media":118724,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":{"0":"post-118785","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-education"},"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts\/118785","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/users\/21830"}],"replies":[{"embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/comments?post=118785"}],"version-history":[{"count":1,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts\/118785\/revisions"}],"predecessor-version":[{"id":118788,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts\/118785\/revisions\/118788"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/media\/118724"}],"wp:attachment":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/media?parent=118785"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/categories?post=118785"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/tags?post=118785"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}