Here we are providing Class 7 Geography Chapter 5 Extra Questions and Answers Water was designed by subject expert teachers. https://ncertmcq.com/extra-questions-for-class-7-social-science/
Water Class 7 Extra Questions Geography Chapter 5
Class 7 Geography Chapter 5 Extra Questions And Answers Question 1.
What is water cycle?
Answer:
The process by which water continually changes its form and circulates between oceans, atmosphere and land is known as water cycle.
Class 7 Geography Chapter Water Extra Questions Question 2.
What is terranium?
Answer:
Terrarium is an artificial enclosure for keeping small house plants.
Class 7 Geography Chapter 5 Extra Questions Question 3.
What is salinity? Also, mention the average salinity of oceans.
Answer:
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.
Class 7 Geography Chapter 5 Worksheet Question 4.
Which are the major sources of freshwater?
Answer:
- Rivers,
- Ponds,
- Springs and
- Glaciers.
Class 7 Geography Ch 5 Extra Questions Question 5.
Why is the water of the oceans salty?
Answer:
The water of the oceans is salty because it contains large amounts of dissolved salts.
Class 7 Geography Water Extra Questions Question 6.
Which two main salts does the ocean water consist?
Answer:
- Sodium chloride and
- Common table salt, which we eat.
Ncert Class 7 Geography Chapter 5 Extra Questions Question 7.
Is all the water on earth available to us?
Answer:
No, all the water on earth is not available to us. Only 2.8 per cent water is fresh, which we can utilize to fulfil our needs. Rest 97.2 per cent water is saline.
Geography Class 7 Chapter 5 Extra Questions Question 8.
If there is more water than land on this earth, why do so many countries face water scarcity?
Answer:
- About 97.2 per cent water is saline.
- Only 2.8 per cent water is fresh which can be utilised by the human beings.
- Uneven distribution of water also leads to water scarcity.
- Careless use and wastage of water by human beings is another main cause of water scarcity.
Class 7 Geography Chapter 5 Short Question Answer Question 9.
How can the movements of oceans be broadly categorised?
Answer:
- Waves,
- tides and
- currents.
Extra Questions For Class 7 Geography Chapter 5 Question 10.
What are waves?
Answer:
Up and down movements of water seen on the surface of an ocean are called waves.
Class 7 Geography Chapter 5 Water Question Answer Question 11.
What is Tsunami?
Answer:
Tsunami is a Japanese word that means “Harbour Waves” as the harbours get destroyed whenever there is Tsunami.
Ch 5 Geography Class 7 Extra Questions Question 12.
Why Tsunami is formed?
Answer:
Tsunami is formed because of the following factors –
- earthquake,
- volcanic eruption,
- underwater landslides.
Class 7 Geography Chapter 5 Question Answer Question 13.
Which part of India got submerge after Tsunami?
Answer:
The Indira point in Andaman and Nicobar islands got submerged after the Tsunami.
Geography Chapter 5 Class 7 Extra Questions Question 14.
When did Tsunami create havoc on the Indian coast?
Answer:
Tsunami or the harbour waves struck havoc in the Indian Ocean on 26th December 2004.
Chapter 5 Geography Class 7 Extra Questions Question 15.
Which parts of India were badly affected by Tsunami?
Answer:
The coastal areas of Andhra Pradesh, Tamil Nadu, Kerala, Pondicherry and the Andaman and Nicobar islands were badly affected by the Tsunami.
Question 16.
Why are Tsunamis rare in the Indian Ocean as compared to the Pacific Ocean?
Answer:
Tsunamis are rare in the Indian Ocean as the seismic activity is less here as compared to the Pacific Ocean.
Question 17.
What is tide?
Answer:
The rhythmic rise and fall of the ocean water twice a day is called a tide.
Question 18.
Distinguish between high tide and low tide.
Answer:
| High tide | Low tide |
| When water covers much of the shore by rising to its highest level, it is called high tide. | When water falls to its lowest level and recedes from the shore, it is called low tide. |
Question 19.
Why tides are caused?
Answer:
The strong gravitational pull exerted by the sun and the moon on the earth’s surface causes the tides.
Question 20.
Why do high tides occur?
Answer:
The water of the earth closer to the moon gets pulled under the influence of the moon’s gravitational force and causes high tide.
Question 21.
Name two types of ocean currents.
Answer:
- Warm current and
- Cold current.
Question 22.
Meeting point of warm and cold current provides the best fishing grounds of the world. Name any two of them.
Answer:
- Seas around Japan and
- Eastern coast of North America.
Question 23.
Give an example of cold and warm current each.
Answer:
Cold current-Labrador ocean current Warm current-Gulf Stream ocean current.
Question 24.
What are spring tides? When do they occur?
Answer:
High magnitude tides are called spring tides. These tides occur on the full moon and new moon nights when the sun, the moon and the earth are in the same line.
Question 25.
What are neap tides? When do they occur?
Answer:
Low magnitude tides are called neap tides. These tides occur when the moon is in its first and last quarter, and the ocean water get drawn in mutually perpendicular directions by the gravitational pull of the sun and the earth resulting in low tides.
Question 26.
Where do the warm and cold ocean currents originate?
Answer:
- The warm ocean currents originate near the equator and move towards the poles.
- The cold currents originate near-polar or higher latitudes and move towards tropical or lower latitudes.
Question 27.
Write the effects of ocean currents.
Answer:
- The ocean current influences the temperature conditions of the area. Warm currents bring about warm temperatures over the land surface.
- The areas where the warm and cold currents meet provide the best fishing grounds of the world.
- The areas where warm and cold currents meet also experience foggy weather making it difficult to navigate.
Question 28.
How are tides helpful to us?
Answer:
- High tides raise the water level at the shores. This helps the ships to arrive at the harbour more easily.
- During high tide, fish come closer to the shore. Thus, it helps in fishing.
- The rise and fall of water due to tides is being used to generate electricity in some places.
Question 29.
Explain the cause of Tsunami which occurred on 26th December 2004.
Answer:
- The Tsunami occurred due to an earthquake on 26th December 2004.
- As the Indian plate went under the Burma plate, there was a sudden movement of the seafloor, causing the earthquake.
- The ocean floor was displaced and tilted in a downward direction.
- A huge mass of ocean water flowed to fill in the gap that was being created by the displacement.
- This marked the withdrawal of the water mass from the coastlines of the landmasses in the south and southeast Asia.
- After thrusting of the Indian plate below the Burma plate, the water mass rushed back towards the coastline. This Tsunami travelled at a speed of about 800 km per hour.
Multiple Choice Questions (MCQs)
1. Which one of the following terms is used for the process by which water continually changes its form and circulates between oceans, atmosphere and land?
(a) Evaporation
(b) Water cycle
(c) Condensation
(d) Precipitation.
Answer:
(b) Water cycle.
2. Which one of the following sources is different from the others with reference to the major sources of freshwater?
(a) Rivers
(b) Oceans
(c) Ponds
(d) Glaciers.
Answer:
(c) Ponds.
3. Which one of the following contains the salty water?
(a) Rivers
(b) Spring
(c) Glacier
(d) Oceans and sea.
Answer:
(d) Oceans and sea.
4. The average salinity of the oceans is;
(a) 35 parts per thousand
(b) 33 parts per thousand
(c) 31 parts per thousand
(d) 39 parts per thousand
Answer:
(a) 35 parts per thousand.
5. How much part of the earth’s surface is covered by water?
(a) One-third
(b) Three-fourth
(c) Two-third
(d) One-fifth.
Answer:
(b) Three-fourth.
6. Which one of the following is different from the other three, with reference to the movements of the ocean water?
(a) Trade wind
(b) Waves
(c) Tides
(d) Currents.
Answer:
(a) Trade wind.
7. In a wave, the ocean water;
(a) rises and falls alternatively
(b) move horizontally
(c) rapidly rise and fall
(d) stay clam.
Answer:
(a) rises and falls alternatively.
8. Which one of the following is caused due to a volcanic eruption or underwater landsliding?
(a) An earthquake
(b) A volcano
(c) Tsunami
(d) Tides
Answer:
(c) Tsunami.
9. Which one of the following part of India get submerged after the Tsunami?
(a) Port Blair
(b) Palk strait
(c) Daman and Diu
(d) Indira Point.
Answer:
(d) Indira Point.
10. How many times the ocean waterfall and rise in a day during a tide?
(a) Twice
(b) Once
(c) Thrice
(d) Four.
Answer:
(a) Twice
11. Why is the tides caused?
(a) Due to gravitational pull of the earth.
(b) Due to gravitational pull exerted by the sun and moon.
(c) Due to gravitational pull of the moon.
(d) Due to continuous movement of ocean water.
Answer:
(b) Due to gravitational pull exerted by the sun and moon.
12. The highest tide is called;
(a) Neap tide
(b) Ocean current
(c) Springtide
(d) Waves.
Answer:
(c) Spring tide.
13. Which one of the following statements is false about the usefulness of tides?
(a) They create water pollution.
(b) They help in navigation.
(c) They help in fishing.
(d) They are used to generate electricity.
Answer:
(a) They create water pollution.
14. Which one of the following terms is used for the streams of water flowing constantly on the ocean floor in a definite path?
(a) Waves
(b) Tides
(c) Current
(d) Tsunami.
Answer:
(c) Current.
15. Which one of the following is a cold current?
(a) Brazilian
(b) Labrador
(c) Gulf stream
(d) Kuroshio
Answer:
(b) Labrador.