Important Questions for CBSE Class 7 Science Chapter 16 - Water: A Precious Resource

Very Short Answer Questions: (1 Marks)

1. When is World Water Day celebrated? What is its significance?

Ans: Every year on March 22nd, World Water Day is celebrated. This is done to draw attention to the world's depleting water resources and the need to conserve them.

2. What is the minimum amount of water recommended by the UN per day?

Ans: The United Nations recommends that each person uses 50 litres of water every day including drinking, cooking, washing, and basic sanitation.

3. What year was celebrated as the International Year of Freshwater and what was its significance?

Ans: The International Year of Freshwater was declared in 2003 to raise awareness about dwindling freshwater supplies and the need for conservation.

4. What is a water table?

Ans: The water table is the upper limit of the soil or earth beneath which the soil is always saturated with water. Water is usually present beneath the water table. The water table level varies from place to place and can fluctuate over time.

5. What is an aquifer?

Ans: Aquifers are underground reservoirs of water held between layers of hard rock beneath the water table. Tube wells and hand pumps can be used to pump out this water.

Short Answer Questions: (2 Marks)

6. How is groundwater recharged? Why is it important?

Ans: The process of infiltration recharges groundwater. Rainwater along with water from ponds, rivers, and lakes, seeps into the ground. Deep beneath the surface, this fills in the empty spaces and gaps between soils. Infiltration is the term for the process of precipitation seeping into the ground. Groundwater recharge is critical for long-term groundwater management and water table stability.

7. What is meant by drip irrigation? Explain its significance?

Ans: Drip irrigation is a form of irrigation that farmers use to save water and manage limited water more efficiently. A network of narrow tubes is put throughout the field with holes that open towards the base of the plants in drip irrigation. The tubes are connected to a water supply source. When water is pumped, the tubes send water only to the plant's base, not the entire field, ensuring that water is used efficiently.

8. What is meant by drip irrigation? Explain its significance?

Ans: Water covers around 71 per cent of the earth's surface. Nearly 97 per cent of this is saltwater or ocean water. Freshwater makes up the remaining 3% of the total. Rivers, lakes, ponds, and glaciers account for 2% of the world's water, while groundwater accounts for 1%.

9. What is rainwater harvesting?

Ans: Rainwater harvesting is the technique of collecting rainwater and using it to recharge groundwater. Rainwater that falls on the ground, rooftops, and other surfaces are channelled through a system of pipes in this manner. This water can be temporarily stored or allowed to permeate the soil and recharge groundwater.

10. Explain the use of bawris in water management.

Ans: Bawris, also known as step wells, are a traditional rainwater gathering device. People use this approach to dig incredibly deep step wells in the ground. These step wells fill up with water when it rains. Since it is so deep, evaporation is minimal. As a result, water may be kept for longer in these wells and utilised in times of scarcity.

Long Answer Questions: (5 Marks)

11. Explain the water cycle with a diagram.

Ans:

The water cycle describes the cyclical movement of water from the earth to the atmosphere and back to the earth through various processes such as evaporation, condensation, and so on.

i. Evaporation: Heat from the sun evaporates water from the earth's surface, including land, oceans, lakes, rivers, and other bodies of water. Water evaporates and rises into the atmosphere.

ii. Transpiration: Water evaporates from the surface of leaves and rises into the air as water vapour.

iii. Condensation: As water vapour climbs higher into the air, it cools and condenses, forming water droplets in the shape of clouds.

iv. Precipitation: When clouds get saturated with water, they rain, snow, hail, or sleet on the ground.

v. Percolation: Some of the rain that falls on the earth is able to percolate into the soil and replenish groundwater.

vi. Water that falls on slopes flows down due to gravity and is finally absorbed.

12. How is the water cycle important in maintaining the water levels on earth? How can we utilise it efficiently to obtain freshwater?

Ans: The water cycle on earth is very important for the earth and all living organisms. The water cycle helps in restoring the water levels on the earth and helps in the generation of flora and fauna in different parts of the land. It helps in restoring the groundwater level which then helps in providing safe drinking and bathing water for individuals. With the help of the water cycle, all the dried out lakes and rivers are also restored that in turn help in the generation of electricity with the help of dams. Rainwater harvesting method is one of the best methods to safely store water. 

13. What are the causes of the depletion of the water table?

Ans: Population growth, urbanisation, industrialisation, and agriculture are the primary causes of water table depletion.

i. Population Explosion: The term "population explosion" refers to a rapid increase in population. As the human population grows, so does our reliance on all resources, including water. The amount of water on the planet is finite, but demand is growing all the time. As a result, we are using up more and more groundwater without permitting enough time to recharge, resulting in its depletion.

ii. Urbanisation: Increased urbanisation and changing lifestyles have increased our need for water even more. Commercialization and a materialistic lifestyle have made us reliant on things that require a large amount of freshwater to produce. This reduces the amount of groundwater available.

iii. Industrialization: As the world's population grows and lifestyles change, new industries emerge to meet our needs and desires. The majority of industrial processes use a lot of water, thereby depleting the groundwater supply.

iv. Agriculture: Plants require a lot of water to grow and reproduce, hence agriculture is a water-intensive industry. Water is more important to some plants than it is to others. In India, the majority of agriculture is still reliant on rain (rain-fed agriculture). Rainstorms, on the other hand, are sporadic and unpredictable. As a direct consequence, more groundwater is being used to make water available for agriculture, further depleting its levels.

What are the Benefits of Important Questions from Vedantu for Class 7 Science Chapter 16 - Water: A Precious Resource

Come on a journey to unravel the significance of water as a precious resource with Vedantu’s Important Questions for Class 7 Science Chapter 16. These important questions act as invaluable tools, guiding students through the complexities of water conservation and promoting a deeper understanding.

1. Conceptual Focus: Pinpoint key water conservation topics for efficient and focused study sessions, ensuring a thorough understanding of the subject.

2. Exam Preparedness: Equip students for exams by aligning questions with the vital aspects of water conservation, reducing stress, and fostering confidence.

3. Fundamental Reinforcement: Strengthen the grasp of fundamental concepts related to water as a precious resource, ensuring a solid foundation for further learning.

4. Time-Effective Learning: Learn to manage time effectively with questions that emphasize essential topics, enabling efficient study sessions and optimal exam preparation.

5. Self-Assessment: Facilitate self-assessment and progress tracking, allowing students to gauge their understanding and identify areas for improvement in water conservation concepts.

6. Strategic Approach: Adopt a strategic approach for higher scores by focusing on crucial topics and practicing questions that align with the chapter's core principles.

7. Comprehensive Coverage: Cover a wide range of water conservation topics, ensuring a holistic understanding of the significance and challenges related to this precious resource.

8. Confidence-Boosting Preparation: Approach exams with confidence, as these questions serve as strategic tools supporting students in mastering the complexities of water conservation and preservation.

Conclusion

Reviewing all the crucial questions for Class 7 Science Chapter 16 - Water: A Precious Resource provides students with a solid grasp of the chapter's topics. The extra and important questions for Class  7 Science Chapter 16 - Water: A Precious Resource engage in a concept-focused discussion encompassing all chapter themes. This question-and-answer method proves time-saving during exam prep, offering an efficient way to revise the chapter and enhance understanding. Practicing these important questions streamlines preparation and boosts confidence for the upcoming exams.