NCERT Solutions For Class 7 Social Science Geography Chapter 5 Water

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water class 7 social scienc georaphy chapter 5
water class 7 social scienc georaphy chapter 5

NCERT Solutions For Class 7 Social Science Geography Chapter 5 Water. We also provide Notes and Lesson Plan. Our Study Rankers specially made them for better understanding. Students may read the NCERT Social Science Geography Chapter 5 PDF to practice concepts with NCERT Solutions and Extra Questions and Answers. We prepared these by keeping in mind the latest CBSE curriculum. Shine among your friends after scoring high in Quiz, MCQ, and Worksheet.

Read more: NCERT Solutions Class 7 Social Science Geography Chapter 1: Environment

Notes of Class 7 Social Science Geography Chapter 5 Water

(Also find NCERT Solutions For Class 7 Social Science Geography Chapter 3 Our Changing Earth given below)

  • We celebrate World Water Day on March 22. On this day, the need to conserve water is reinforced in different ways.
  • The sun’s heat causes evaporation of water vapour.
  • When the water vapour cools down, it condenses and forms clouds.
    • From there it may fall on the land or sea in the form of rain, snow or sleet.
  • Water Cycle is the process by which water continually changes its form and circulates between oceans, atmosphere and land.
NCERT Solutions Class 7 Social Science Geography Water Water Cycle
Water Cycle
  • Our earth is like a terrarium.
    • Terrarium is an artificial enclosure for keeping small house plants.
NCERT Solutions Class 7 Social Science Geography Water Terrariums
A variety of Terrariums
  • The major sources of fresh water are the rivers, ponds, springs and glaciers.
  • The ocean bodies and the seas contain salty water.
    • The water of the oceans is salty or saline as it contains large amount of dissolved salts.
    • Most of the salt is sodium chloride or the common table salt that you eat.

Distribution of Water Bodies

Water covers three-fourth of the earth surface.

Water BodiesDistribution(%)Is Water Fit For Use?
Oceans97.3Saline Water
Ice caps2.0Fresh Water
Groundwater0.68Fresh Water
Freshwater lakes0.009Fresh Water
Inland seas and Salt lakes0.009Fresh Water
Atmosphere0.0019Fresh Water
Rivers0.0001Fresh Water
TOTAL100.00

You must be aware of this distribution from NCERT Class 7 Geography Our Changing Earth

Ocean Circulation

  • Ocean water keeps moving continuously. It is never still.
  • The movements that occur in oceans can be broadly categorised as:
    1. Waves
    2. Tides
    3. Currents.

Waves

  • When the water on the surface of the ocean rises and falls alternately, they are called waves.
NCERT Solutions Class 7 Social Science Geography Water Waves
Waves
  • Winds scrape across the ocean surface to form waves.
  • The stronger the wind blows, the bigger the wave becomes.
  • During a storm, the winds blowing at very high speed form huge waves.
    • These may cause tremendous destruction.
      • An earthquake, a volcanic eruption or underwater landslides can shift large amounts of ocean water.
      • As a result a huge tidal wave called tsunami, that may be as high as 15m., is formed.
      • The largest tsunami ever measured was 150m. high.
      • These waves travel at a speed of more than 700 km. per hour.
      • India’s southern most part – Indira Point – suffered a massive tsunami on 26 December 2004.
NCERT Solutions Class 7 Social Science Geography Water Indira Point
Indira Point

Tides

  • The rhythmic rise and fall of ocean water twice in a day is called a tide.
    • It is high tide when water covers much of the shore by rising to its highest level.
      • High tides help in navigation.
      • They raise the water level close to the shores.
      • This helps the ships to arrive at the harbour more easily.
      • The high tides also help in fishing. Many more fish come closer to the shore during the high tide. This enables fishermen to get a plentiful catch.
    • It is low tide when water falls to its lowest level and recedes from the shore.
NCERT Solutions Class 7 Social Science Geography Water High Tide and Low Tide
High Tide vs. Low Tide
  • The strong gravitational pull exerted by the sun and the moon on the earth’s surface causes the tides.
    • The water of the earth closer to the moon gets pulled under the influence of the moon’s gravitational force and causes high tide.
    • During the full moon and new moon days, the sun, the moon and the earth are in the same line and the tides are highest.
      • These tides are called spring tides.
    • But when the moon is in its first and last quarter, the ocean waters get drawn in diagonally opposite directions by the gravitational pull of sun and earth resulting in low tides.
      • These tides are called neap tides.
NCERT Solutions Class 7 Social Science Geography Water Spring Tide and Neap Tide
Spring Tide vs. Neap Tide
  • The rise and fall of water due to tides is being used to generate electricity in some places.

Ocean Currents

  • These are streams of water flowing constantly on the ocean surface in definite directions.
Ocean Currents
Ocean Currents
  • The ocean currents may be warm or cold.
    • 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.
      • The Labrador Ocean current is cold current while the Gulf Stream is a warm current.
  • The ocean current influence the temperature conditions of the area.
    • Warm currents bring about warm temperature over land surface.
  • The areas where the warm and cold currents meet provide the best fishing grounds of the world.
    • Seas around Japan and the eastern coast of North America are such examples.
  • The areas where a warm and cold current meet also experience foggy weather making it difficult for navigation.

NCERT Solutions For Class 7 Social Science Geography Chapter 5 Water

(Also find NCERT Solutions For Class 7 Social Science Geography Chapter 3 Our Changing Earth given below)

Q. 1. Answer the following questions briefly.

  1. What is precipitation?
  2. Define water cycle?
  3. What are the factors affecting the height of the waves?
  4. Which factors affect the movement of ocean water?
  5. What are tides and how are they caused?
  6. What are ocean currents?
A)
  1. Rain, snow, sleet, or hail that falls to or condenses on the ground is called precipitation.
  2. Water Cycle is the process by which water continually changes its form and circulates between oceans, atmosphere and land.
  3. The stronger the wind blows, the bigger the wave becomes. An earthquake, a volcanic eruption or underwater landslides can shift large amounts of ocean water.
  4. The factors that affect the movements of ocean water are;
    1. Temperature
    2. Winds
    3. The gravitational pull of the sun
    4. The earth
    5. The moon
    6. Warm and cold currents
  5. The rhythmic rise and fall of ocean water twice in a day is called a tide. It is caused by the strong gravitational pull exerted by the sun and the moon on the earth’s surface.
  6. Ocean Currents are streams of water flowing constantly on the ocean surface in definite directions.

Q. 2. Give reasons:

  1. Ocean water is salty.
  2. The quality of water is deteriorating.
A)
  1. The water of the oceans is salty or saline as it contains large amount of dissolved salts. Most of the salt is sodium chloride or the common table salt.
  2. Quality of water is deteriorating because humans discharge wastes into different water bodies. Some common waste discharge includes: industrial effluents, untreated water of industries, sewerage water etc.

Q. 3. Tick the correct answer.

  • The process by which water continually changes its form and circulates between oceans, atmosphere and land
    1. Water cycle
    2. Tidess
    3. Ocean currents.

A) 1. Water Cycle

  • Generally the warm ocean currents originate near
    1. Poles
    2. The Equator
    3. None of these.

A) 2. The Equator

  • The rhythmic rise and fall of ocean water twice in a day is called
    1. Tide
    2. Ocean current
    3. Wave

A) 1. Tide

Q. 4. Match the following:

Column IColumn II
(i)Caspian Sea(a)Periodic rise and fall of water
(ii)Tide(b)Largest lake
(iii)Tsunami(c)Streams of water moving in definite paths
(iv)Ocean Currents(d)Strong seismic waves
A)
Column IColumn II
(i)Caspian Sea(b)Largest lake
(ii)Tide(a)Periodic rise and fall of water
(iii)Tsunami(d)Strong seismic waves
(iv)Ocean Currents(c)Streams of water

FAQ

(Here you can find the NCERT Solutions For Class 7 Social Science Geography Chapter 3 Our Changing Earth FAQs.)

Q. 1. Define Salinity.

A) Salinity is the amount of salt in grams present in 1000 grams of water. The average salinity of the oceans is 35 parts per thousand.

Q. 2. How come swimmers float in Dead Sea of Israel?

A) Swimmers can float in it because the increased salt content makes it dense. It’s salinity is 340 grams per litre.

Q. 3. If there is more water than land on this earth, why do so many countries face water scarcity?

A) Out of all the water on earth’s surface, only freshwater is fit for use which is roughly 0.006% of all water found on the earth. Therefore, a huge population suffer from water shortage.

NCERT Solutions For Class 7 Social Science Geography Chapter 5 Water Conclusion:

Above written includes NCERT Solutions For Class 7 Social Science Geography Chapter 5 Water, detailed Explanation, and Question Answers. Browse our site for various detailed and easy NCERT Solutions and CBSE Notes.

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