CBSE Class 4 EVS A Rivers Tale Worksheet Set 01

Question 1. Give examples for each of the following: Three pollutants of water, Three sources of water, Three water animals
Answer:
- Three pollutants of water: 1. Industrial waste and chemicals, 2. Domestic sewage and detergents, 3. Plastic waste and garbage.
- Three sources of water: 1. Rain, 2. Rivers, 3. Underground water (wells and tube wells).
- Three water animals: 1. Fish, 2. Whale, 3. Octopus.
In simple words: Water pollutants make water dirty, sources give us water, and water animals live inside water.
Exam Tip: Always categorize your answers clearly with bullet points or numbers when multiple items are asked in a single question.

Question 2. Name and draw three ways of cleaning water at home:
Answer:
1. Boiling - Heating water to kill harmful germs and bacteria.
2. Filtering - Passing water through a cloth, fine mesh, or a water filter to remove solid impurities.
3. Using water purifiers (RO/UV filters) - Using electric purification systems to remove dissolved impurities and micro-organisms.
*(Note: Students should draw simple sketches of a boiling pot on a stove, a cloth filter funnel setup, and an electric water purifier in the boxes provided).*
In simple words: We clean drinking water at home by boiling it, filtering it, or using a machine purifier.
Exam Tip: Mention both the method name and a brief one-line description of how it works to secure full marks.

Question 3. Paste a picture of drought and a picture of water shortage. Also write the differences between the two situations.
Answer:
Differences between drought and water shortage:
- Drought: It is a natural disaster caused by a long period of continuous below-average rainfall, leading to severe lack of water for drinking, crops, and livestock over an entire region.
- Water shortage: It is a condition where there is an inadequate supply of water to meet the demands of a population, which can happen due to wastage, poor management, pipeline leaks, or overuse, even in areas with normal rainfall.
*(Note: Students should paste pictures showing cracked dry earth for drought, and people standing in queues with buckets around a water tanker for water shortage).*
In simple words: Drought is a severe lack of rain causing dry land everywhere, while water shortage means there is not enough water supplied to people for daily needs.
Exam Tip: Clearly contrast the root cause (natural lack of rain vs. scarcity or mismanagement of supply) when asked for differences between drought and water shortage.

Question 1. Write two slogans to save water:
Answer:
1. Save water today, and it will save you tomorrow!
2. Every drop counts - Conserve water, preserve life!
In simple words: Slogans are catchy lines that remind people not to waste water.
Exam Tip: Keep slogans short, rhyming, and impactful with exclamation marks.

Question 2. What is 'Rain water harvesting'? Name cities of India in which this system is being used?
Answer:
Rain water harvesting is the technique of collecting, filtering, and storing rainwater from rooftops or open spaces for reuse instead of allowing it to run off wastefully.
Cities in India where this system is widely used include Chennai, Bengaluru, Delhi, and Mumbai.
In simple words: Rain water harvesting means catching and saving rainwater so we can use it later.
Exam Tip: Remember to define the process clearly and list at least two major Indian cities like Chennai and Bengaluru.

Question 3. Name and draw two manmade and two natural sources of water.
Answer:
- Two manmade sources of water: 1. Dams, 2. Hand pumps / Tube wells.
- Two natural sources of water: 1. Rivers, 2. Lakes / Oceans.
*(Note: Students should draw sketches of a dam and a handpump under the 'Manmade' section, and a river and a lake under the 'Natural' section).*
In simple words: Natural sources are made by nature like rivers, and manmade sources are built by humans like dams.
Exam Tip: Double-check your classification so that natural features are not mixed up with human-constructed water structures.

Question 4. Write down the differences between river, sea and ocean.
Answer:
- River: A natural flowing watercourse, usually of freshwater, flowing towards an ocean, sea, lake, or another river.
- Sea: A large body of salty water that is smaller than an ocean and is partly enclosed by land.
- Ocean: A vast, continuous body of saline water that covers the major part of the Earth's surface and is much larger and deeper than a sea.
In simple words: A river flows in a channel, a sea is a large salty water body near land, and an ocean is the largest and deepest body of salt water on Earth.
Exam Tip: Differentiate them based on size, water type (fresh vs. salty), and boundaries (flowing channel vs. enclosed water body vs. vast global expanse).

Question 5. How does the river water get polluted?
Answer:
River water gets polluted due to various human activities, such as:
1. Dumping industrial waste and toxic chemicals directly from factories into the river.
2. Releasing untreated domestic sewage and household wastewater into water bodies.
3. Bathing cattle, washing clothes, and throwing plastic garbage and religious offerings into the water.
4. Agricultural runoff containing harmful chemical fertilizers and pesticides.
In simple words: River water becomes dirty when factories, homes, and people dump garbage, chemicals, and sewage into it.

Fill in the blanks:-

1. The first European invader of Indian soil ___________.

2. The first person to reach the North pole by over land journey ___________.

3. Air Force Day is celebrated on _______.

4. The largest diamond in the world is _________.

5. The old name of Indonesia is __________.

6. This is called the Land of Morning Calm ________.

7. It is the brightest star _______.

8. It is the national emblem of USA __________.

9. The full form of TERI is ______.

10. The World Forest Day is celebrated on _______.

11. Which state is called orchid paradise in India? _______.

12. Which is the capital of Egypt? _______.