NCERT Solutions for Class 7 Social Science - Water

Q1:Answer the following questions. 

(i) What is precipitation?


Ans: Precipitation is when rain, snow, hail, or other things fall from the sky to the ground. These droplets or ice crystals get too heavy, they can't stay up in the air, so they fall to the Earth's surface. It's like when raindrops become too big or snowflakes stick together and become too heavy, they come down and reach the ground. 

(ii) What is the water cycle? 
Ans: The water cycle is a constant and repeating process where water changes and moves around the Earth. It goes from oceans to the air as clouds and vapor, then comes down to the land as rain or other forms of precipitation, filling up rivers, lakes, and underground areas. This cycle keeps going in a continuous loop.
Water cycle

(iii) What are the factors affecting the height of the waves?
Ans: Factors affecting the height of the waves: 

1. Speed off wind
2. Duration of wind
3. The distance the wind blows over water

(iv) Which factors affect the movement of ocean water? 
Ans: Factors affecting the movement of ocean water:

1. Temperature
2. Earthquake or volcanic eruption
3. The gravitational pull of the sun and the moon
4. Underwater landslides

(v) What are tides and how are they caused? 
Ans: 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 surface of the earth causes the tides.Spring Tides and Neap Tides

(vi) What are ocean currents?
Ans: Ocean currents are like flowing streams in the ocean that move water in specific directions. There are two main types: warm currents, which flow from the equator towards the poles, and cold currents, which flow from the poles towards the equator. These currents play a crucial role in redistributing heat around the planet and have a significant impact on climate and marine life. 

Q2: Give reasons.

Q3: Tick the correct answer. 

(i) The process by which water continually changes its form and circulates between oceans, atmosphere, and land 
(a) Water cycle
(b) Tides
(c) Ocean currents
Ans: (a) Water cycle

(ii) Generally the warm ocean currents originate near 
(a) Poles
(b) Equator
(c) None of these
Ans: (b) Equator

(iii) The rhythmic rise and fall of ocean water twice in a day is called 
(a) Tide
(b) Ocean current
(c) Wave
Ans: (a) Tide

Q4: Match the following.

Ans: