Right Answer for MCQ will be highlighted on Hover / Click on the option.
- Life on Earth relies on essential resources such as soil, water, air, and the energy provided by the Sun.
- Winds are created due to the uneven heating of air over land and water surfaces.
- Water evaporates from bodies of water and later condenses to produce rainfall.
- Rainfall patterns are influenced by the dominant wind conditions in a given region.
- Nutrients are continuously recycled, helping to maintain a balance among the different elements of the biosphere.
- Air, water, and soil pollution degrade the quality of life and negatively impact biodiversity.
- It is important to conserve natural resources and use them sustainably for the future.
NCERT Based MCQ with Explanation:
1. What percentage of the Earth's surface is covered by water?
(A) 50%
(B) 60%
(C) 70%
(D) 75%
Explanation: The Earth is covered by water bodies, primarily oceans, which account for about 75% of its surface, as highlighted in the document.
2. What is the Earth's outer crust called?
(A) Atmosphere
(B) Lithosphere
(C) Hydrosphere
(D) Biosphere
Explanation: The Earth's outer crust, consisting of solid rock, is referred to as the lithosphere. It forms a key part of the Earth's structure, supporting various life forms.
3. What is the biosphere?
(A) A mixture of gases in the air
(B) The zone where life exists on Earth
(C) A part of the Earth's core
(D) A region where water meets air
Explanation: The biosphere is the life-supporting zone on Earth, where the atmosphere, hydrosphere, and lithosphere interact to enable life.
4. What is the major component of the atmosphere on Venus and Mars?
(A) Oxygen
(B) Nitrogen
(C) Carbon dioxide
(D) Water vapor
Explanation: Unlike Earth, where life alters the composition of the atmosphere, the atmospheres of Venus and Mars are dominated by carbon dioxide, making up 95-97% of their atmospheres.
5. How do green plants help in reducing the amount of carbon dioxide in the atmosphere?
(A) By absorbing oxygen
(B) Through respiration
(C) By photosynthesis
(D) By evaporating water
Explanation: Green plants use sunlight to convert carbon dioxide into glucose through the process of photosynthesis, thereby helping to reduce CO2 levels in the atmosphere.
6. Which gas constitutes the largest percentage of the Earth's atmosphere?
(A) Oxygen
(B) Carbon dioxide
(C) Nitrogen
(D) Hydrogen
Explanation: Nitrogen makes up the largest proportion of the Earth's atmosphere, constituting approximately 78%, as indicated in the document.
7. How does the atmosphere act as a blanket?
(A) By blocking all sunlight
(B) By allowing heat to escape quickly
(C) By maintaining a stable temperature
(D) By reflecting heat back to space
Explanation: The atmosphere helps in keeping the Earth's temperature fairly stable by preventing sudden temperature changes, both during the day and at night.
8. What is the primary cause of wind movement?
(A) Rotation of the Earth
(B) Uneven heating of air
(C) Presence of mountains
(D) Gravitational pull of the moon
Explanation: Winds are primarily caused by the uneven heating of air over land and water bodies, which creates pressure differences, leading to air movement.
9. How are clouds formed?
(A) By the heating of water vapor
(B) By the condensation of water vapor
(C) Through photosynthesis
(D) By the cooling of water bodies
Explanation: Clouds form when water vapor in the air rises, cools, and condenses into tiny droplets, which cluster together to create clouds.
10. What leads to the formation of rain?
(A) Expansion of air
(B) Condensation of water vapor
(C) Evaporation of water
(D) Rotation of the Earth
Explanation: Rain occurs when water vapor in the atmosphere condenses into water droplets that grow in size and fall to the Earth as precipitation.
11. What creates convection currents in the atmosphere?
(A) Movement of the Earth’s plates
(B) Rotation of the Earth
(C) Uneven heating of land and water
(D) Evaporation of water bodies
Explanation: Convection currents in the atmosphere are caused by the uneven heating of land and water, leading to the rise of warm air and movement of cooler air into those regions.
12. Which factor primarily controls wind patterns?
(A) Earth's gravity
(B) Rotation of the Earth
(C) Temperature of the oceans
(D) Windmills
Explanation: In addition to uneven heating, the Earth's rotation influences wind direction and patterns, leading to phenomena such as trade winds and jet streams.
13. Why does land heat faster than water?
(A) Land absorbs more sunlight
(B) Water reflects sunlight
(C) Land is a better conductor of heat
(D) Water takes longer to warm up due to its specific heat capacity
Explanation: Water has a high specific heat capacity, which means it heats up and cools down more slowly than land, causing land to heat faster during the day.
14. Which direction does wind blow during the day in coastal areas?
(A) From land to sea
(B) From sea to land
(C) From mountains to plains
(D) From plains to mountains
Explanation: During the day, the land heats up faster than the sea, causing warm air to rise over the land. Cooler air from the sea moves into the low-pressure area over the land, creating a sea breeze.
15. What is smog?
(A) A type of fog
(B) A mixture of smoke and fog
(C) Rain mixed with dust
(D) Condensed water vapor
Explanation: Smog is a type of air pollution caused by a mixture of smoke and fog, often worsened by industrial emissions and vehicle exhaust, especially in colder weather.
16. What is the main cause of acid rain?
(A) Oxides of nitrogen and sulfur
(B) Carbon dioxide
(C) Ozone layer depletion
(D) Evaporation of water bodies
Explanation: Acid rain is caused when oxides of nitrogen and sulfur, primarily released from burning fossil fuels, dissolve in rainwater and form acids, which then fall as precipitation.
17. What are the main components of the hydrosphere?
(A) Soil and water
(B) Oceans, seas, and rivers
(C) Water bodies and the atmosphere
(D) Mountains and lakes
Explanation: The hydrosphere consists of all the water bodies on Earth, including oceans, seas, rivers, lakes, and underground water.
18. What is air pollution?
(A) An increase in oxygen levels
(B) Presence of unwanted substances in the air
(C) More water vapor in the atmosphere
(D) Only human activities affecting air quality
Explanation: Air pollution refers to the presence of harmful or undesirable substances like gases, smoke, or chemicals that lower air quality and harm living organisms.
19. How does soil support plant life?
(A) By holding plant seeds
(B) By providing water and nutrients
(C) By maintaining the temperature of roots
(D) By blocking sunlight
Explanation: Soil is essential for plant growth because it supplies nutrients and water necessary for their metabolic processes.
20. What is soil erosion?
(A) The formation of soil
(B) The movement of soil from one place to another
(C) Soil being washed away by water or wind
(D) The addition of nutrients to soil
Explanation: Soil erosion occurs when the top layer of soil is removed or carried away by wind or water, often leaving the land barren and reducing its fertility.
21. What factors contribute to soil erosion?
(A) Trees and vegetation
(B) Slow-moving rivers
(C) Wind and water
(D) Presence of humus
22. What is humus?
(A) A type of soil
(B) Decayed organic matter in soil
(C) A nutrient in water
(D) A type of clay
23. Which of the following is a renewable natural resource?
(A) Fossil fuels
(B) Minerals
(C) Solar energy
(D) Plastic
24. How does deforestation affect soil?
(A) Increases soil nutrients
(B) Prevents soil erosion
(C) Increases soil erosion
(D) Adds more humus to the soil
25. Why is nitrogen essential for life?
(A) It makes up 21% of the atmosphere
(B) It is used by plants for respiration
(C) It is a part of DNA, proteins, and vitamins
(D) It helps in photosynthesis
26. How do nitrogen-fixing bacteria benefit plants?
(A) By producing oxygen
(B) By converting nitrogen into nitrates
(C) By absorbing carbon dioxide
(D) By providing sunlight
27. What is the primary process responsible for the cycling of carbon in the atmosphere?
(A) Nitrogen fixation
(B) Photosynthesis
(C) Water cycle
(D) Soil erosion
28. Which gas is a significant contributor to the greenhouse effect?
(A) Nitrogen
(B) Oxygen
(C) Carbon dioxide
(D) Argon
29. What is the role of ozone in the atmosphere?
(A) To block sunlight
(B) To trap oxygen in the atmosphere
(C) To absorb harmful ultraviolet radiation
(D) To form greenhouse gases
30. Which human activities are primarily responsible for increasing carbon dioxide levels?
(A) Photosynthesis and respiration
(B) Deforestation and burning fossil fuels
(C) Water conservation and recycling
(D) Oxygen production and nitrogen fixation
0 Response to "Science MCQ, Class 9th, Chapter-14, Natural Resources"
Post a Comment