CBSE Class 7 - Geography - Ch5 - Water (Short Q and A)

WATER

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Short Q & A based on NCERT Chapter

Q1: What is precipitation?

Answer: The condensation of water vapour in the form of water droplets or ice-crystals and its falling on the earth’s surface is known as precipitation.


Q2: Define glacier.

Answer: The moving mass of ice is called glacier.


Q3: What is the taste of sea water?

Answer: The taste of sea water is salty.


Q4: Why is sea water saline?

Answer: Sea water is saline due to the dissolution of large amount of salt in it.




Q5: How sea tides are caused?

Answer: Sea tides are caused due to the attraction of moon and to some extent that of the sun.


Q6: What is a tide?

Answer: The periodic rise and fall of the sea water is called tide.
Tides are of two types:
(a) High Tides,
(b) Low Tides.


Q7: Name three kinds of water movement.

Answer: The three kinds of water movement are:

• Waves, 
• tides and 
• currents.

Q8: How much area of the earth is covered by water?

Answer: About 71% area of the earth’s surface is covered by water.


Q9: Name the continents which are surrounded by Atlantic Oceans.

Answer: Atlantic Ocean covers (surrounded) the following continents:
(a) North America
(b) South America
(c) Europe
(d) Africa


Q10: Which ocean provides the busiest sea transport route between North America and Europe?

Answer:  Atlantic Ocean provides the busiest sea transport route between North America and Europe.


Q11: Which ocean is shaped like ‘S’ and how much area of the earth’s surface is covered by it?

Answer: The Atlantic Ocean is in ‘S’ shaped and it covers the total 1/6th surface of the earth.


Q12: What are the importance of oceans?

Answer: The importance of the oceans:

1. They enjoy a direct influence over the temperature. In regulating the temperature, closeness to the ocean is a major factor.
2. A free and permanent route for travel and trade is provided with us by the oceans.
3. In the form of waves, they have an immense energy sources.
4. Oceans are main sources of fishes and other edible marine life.

Q13: What are the characteristics of warm current?

Answer: The characteristics of warm current:

1. It comes from equatorial regions.
2. The temperature of the coastal areas are gone up by warm currents.
3. Warm currents help in navigation.
4. Warm currents keep the port even in the polar region free from ice.

Q14: Distinguish between waves and tides.

Answer:

	Waves	Tides
1.	Waves occur by the pushing action of the winds.	Tides occur mainly by the attraction of the moon and to some extent that of the sun.
2.	In wave-motion, the surface water heaves up and down gently or violently according to the weather conditions.	In tide motion sea-water rises twice a day and falls twice at regular intervals.
3.	Stormy waves may cause disasters.	Tides are very helpful in trading, fishing and navigation.

Q15: How can you distinguish between a warm current and a cold current?

Answer:

Warm current	Cold current
1. Warm currents flow from the low latitudes towards the high latitudes.	1. Cold currents flow from the high latitudes towards the low latitudes.
2. A warm current raises the temperature of nearby areas by making the place warmer.	2. A cold current makes the nearby places colder.
3. Winds passing over the warm currents absorb a good deal of moisture and bring heavy rainfall over the coastal regions.	3. Winds passing over the cold currents become dry and cool and bring little or only scanty rainfall to the coastal areas.
4. Warm currents help melting of iceberg and thus remove a menace to navigation.	4. Cold currents create more icebergs and hence hinder navigation.
5. Warm currents keep the ports free from ice in winter in higher latitudes.	5. Cold currents help in freezing coastal waters in higher latitudes.

✎Note: You can check Water NCERT Chapter Solutions here.