Questions & Answers - CBSE Class 9 (60 from NCERT PDF)
20 Short (2M), 20 Medium (4M), 20 Long (8M) based on PDF exercises/content.
Short Questions (2 Marks Each) - 20 Total
1. Largest basin India? (PDF p.17)
Answer: Ganga.
2. Indus length? (PDF p.18)
Answer: 2900 km.
3. Ganga length? (PDF p.20)
Answer: Over 2500 km.
4. Brahmaputra known Tibet? (PDF p.20)
Answer: Tsang Po.
5. Narmada origin? (PDF p.21)
Answer: Amarkantak.
6. Godavari length? (PDF p.21)
Answer: 1500 km.
7. Mahanadi length? (PDF p.21)
Answer: 860 km.
8. Krishna length? (PDF p.22)
Answer: 1400 km.
9. Kaveri length? (PDF p.22)
Answer: 760 km.
10. Largest freshwater lake? (PDF p.22)
Answer: Wular.
11. Sundarban name from? (PDF p.20)
Answer: Sundari tree.
12. Majuli? (PDF p.21)
Answer: World's largest riverine island.
13. Shivasamudram? (PDF p.22)
Answer: Second biggest waterfall India.
14. GAP year? (PDF p.23)
Answer: 1985.
15. NRCP year? (PDF p.23)
Answer: 1995.
16. Namami Gange year? (PDF p.20)
Answer: 2014.
17. Indus Treaty year? (PDF p.18)
Answer: 1960.
18. Dakshin Ganga? (PDF p.21)
Answer: Godavari.
19. Salt lake example? (PDF p.22)
Answer: Sambhar.
20. Artificial lake example? (PDF p.23)
Answer: Guru Gobind Sagar.
Medium Questions (4 Marks Each) - 20 Total
1. Drainage basin? (PDF p.17)
Answer: A drainage basin is the area drained by a single river system, where small streams from different directions converge to form the main river that drains into a larger water body like a lake, sea, or ocean. It is separated from adjacent basins by elevated areas such as mountains or uplands, known as water divides. For example, the Amazon river has the world's largest drainage basin.
2. Himalayan vs Peninsular? (PDF p.17)
Answer: Himalayan rivers are perennial, receiving water from rain and melted snow, with long courses, deep gorges, and forming deltas. Peninsular rivers are mostly seasonal, dependent on rainfall, with shorter and shallower courses, and many form estuaries instead of deltas. The Himalayan rivers originate from the north of the mountain ranges, while Peninsular ones originate from the Western Ghats or central highlands.
3. Indus tributaries? (PDF p.18)
Answer: The Indus river's tributaries include the Zaskar, Nubra, Shyok, and Hunza in the Kashmir region. Further downstream, it is joined by the Satluj, Beas, Ravi, Chenab, and Jhelum near Mithankot in Pakistan. These tributaries contribute to the river's flow and form a significant river system.
4. Ganga formation? (PDF p.18)
Answer: The Ganga river is formed by the headwaters called Bhagirathi, fed by the Gangotri Glacier, joining the Alaknanda at Devaprayag in Uttarakhand. It emerges from the mountains onto the plains at Haridwar. This confluence marks the beginning of the main Ganga river system.
5. Ganga tributaries Himalayan? (PDF p.20)
Answer: The major Himalayan tributaries of the Ganga are the Yamuna (from Yamunotri Glacier), Ghaghara, Gandak, and Kosi (from Nepal Himalaya). These rivers flood the northern plains annually, causing damage but also enriching the soil for agriculture. The Yamuna meets the Ganga at Allahabad as a right bank tributary.
6. Ganga tributaries Peninsular? (PDF p.20)
Answer: The main Peninsular tributaries of the Ganga are the Chambal, Betwa, and Son, rising from semi-arid areas. They have shorter courses and carry less water compared to Himalayan ones. These rivers ultimately join the Ganga, contributing to its flow in the plains.
7. Sundarban Delta? (PDF p.20)
Answer: The Sundarban Delta is formed by the Ganga and Brahmaputra rivers, named after the Sundari tree that grows in marshland. It is the world's largest and fastest-growing delta, located in the Bay of Bengal. It is home to the Royal Bengal tiger and features deltaic plains.
8. Brahmaputra features? (PDF p.20)
Answer: The Brahmaputra has a braided channel throughout its length in Assam, forming many riverine islands like Majuli. It carries large volumes of water and silt due to high rainfall in India, leading to frequent floods and channel shifts. In Tibet, it carries less silt as it is a cold, dry area.
9. Narmada features? (PDF p.21)
Answer: The Narmada flows through a rift valley, creating picturesque locations like the Marble rocks near Jabalpur and Dhuadhar falls. Its tributaries are short and join at right angles. The basin covers parts of Madhya Pradesh and Gujarat.
10. Godavari tributaries? (PDF p.21)
Answer: The Godavari is joined by tributaries like Purna, Wardha, Pranhita, Manjra, Wainganga, and Penganga, with the last three being very large. Known as Dakshin Ganga due to its length and coverage. The basin spans Maharashtra, Madhya Pradesh, Odisha, and Andhra Pradesh.
11. Kaveri falls? (PDF p.22)
Answer: The Kaveri forms the Shivasamudram Falls, the second biggest waterfall in India. Hydroelectric power from these falls supplies Mysuru, Bengaluru, and the Kolar Gold Field. The river reaches the Bay of Bengal south of Cuddalore in Tamil Nadu.
12. Lakes types? (PDF p.22)
Answer: Lakes can be permanent or seasonal, glacial (Himalayan origin), tectonic (Wular), oxbow (from meandering rivers), lagoons (coastal like Chilika), or artificial (dams like Guru Gobind Sagar). Some are saltwater like Sambhar, used for salt production. India has diverse lakes differing in size and characteristics.
13. Lakes importance? (PDF p.23)
Answer: Lakes regulate river flow by preventing flooding during heavy rains and maintaining flow in dry seasons. They are used for hydel power generation, moderate surrounding climate, support aquatic ecosystems, enhance natural beauty, develop tourism, and provide recreation. Examples include Dal Lake for tourism in Kashmir.
14. Rivers economy? (PDF p.23)
Answer: Rivers provide essential water resources for human activities like irrigation, navigation, and hydro-power generation, crucial for India's agriculture-dependent economy. Settlements and cities have developed along riverbanks since ancient times. They are fundamental to livelihood for the majority of the population.
15. Pollution causes? (PDF p.23)
Answer: Growing domestic, municipal, industrial, and agricultural demands drain river volume, while untreated sewage and effluents are emptied into rivers. This affects water quality and reduces the river's self-cleansing capacity. For example, the Ganga can assimilate pollution within 20 km, but urbanization prevents this.
16. NRCP objective? (PDF p.23)
Answer: The National River Conservation Plan (NRCP), launched in 1995, aims to improve the water quality of major rivers through pollution abatement works. It expanded the Ganga Action Plan to cover other rivers. The plan focuses on cleaning rivers that are key water sources in the country.
17. West flowing Peninsular? (PDF p.21)
Answer: The major west-flowing Peninsular rivers are the Narmada and Tapi, which flow through rift valleys and form estuaries. Other short west-flowing rivers include Sabarmati, Mahi, Bharathpuzha, and Periyar. They drain water from states like Madhya Pradesh, Gujarat, and Maharashtra.
18. East flowing smaller? (PDF p.22)
Answer: Smaller east-flowing rivers include the Damodar, Brahmani, Baitarni, and Subarnrekha, which flow towards the Bay of Bengal. They are notable examples besides major ones like Godavari. Locate them on an atlas for better understanding.
19. Salt water lake? (PDF p.22)
Answer: The Sambhar lake in Rajasthan is a saltwater lake, sometimes seasonal in inland drainage regions. Its water is used for producing salt. It differs from freshwater lakes like Wular or Dal.
20. Tectonic lake? (PDF p.22)
Answer: The Wular lake in Jammu and Kashmir is a tectonic lake, formed due to tectonic activity. It is the largest freshwater lake in India. Unlike glacial lakes, it results from earth's movements.
Long Questions (8 Marks Each) - 20 Total
1. Wular lake state? (PDF p.24, NCERT Q1(i))
Answer: The Wular lake is located in Jammu and Kashmir. It is the largest freshwater lake in India and is of tectonic origin, formed due to tectonic activity where glaciers dug out a basin later filled with snowmelt. Unlike other Himalayan lakes which are mostly glacial, Wular contrasts with saltwater lakes like Sambhar in Rajasthan or artificial ones like Gobind Sagar. In exams, highlight its significance in the Himalayan region and compare with Punjab, Uttar Pradesh, or Rajasthan options to explain why Jammu and Kashmir is correct. This lake supports local ecosystem and tourism, emphasizing India's diverse lake formations.
2. Narmada source? (PDF p.24, NCERT Q1(ii))
Answer: The river Narmada has its source at Amarkantak in Madhya Pradesh. It rises in the Amarkantak hills and flows westwards through a rift valley formed due to faulting, creating picturesque locations like Marble rocks and Dhuadhar falls. This differs from other options like Satpura (nearby but not source), Brahmagiri (Kaveri source), or Western Ghats slopes (Godavari/Krishna). The Narmada basin covers Madhya Pradesh and Gujarat, with short tributaries joining at right angles. Discuss its unique west flow among Peninsular rivers and conservation efforts like Namami Devi Narmade for full marks.
3. Salt water lake? (PDF p.24, NCERT Q1(iii))
Answer: Sambhar is a saltwater lake located in Rajasthan, used for producing salt from its seasonal waters in inland drainage basins. It contrasts with freshwater lakes like Dal (Kashmir), Wular (largest freshwater, tectonic), or Gobind Sagar (artificial dam lake). Sambhar is sometimes seasonal in semi-arid regions, highlighting India's diverse lake types. In answers, explain formation in inland drainage and economic use (salt production), differentiating from glacial or tectonic lakes for comprehensive understanding.
4. Longest Peninsular river? (PDF p.24, NCERT Q1(iv))
Answer: The Godavari is the longest river of Peninsular India, about 1500 km, rising from Western Ghats in Nasik, Maharashtra, and draining into the Bay of Bengal. Known as Dakshin Ganga, its basin is the largest among Peninsular rivers, covering Maharashtra (50%), Madhya Pradesh, Odisha, and Andhra Pradesh. Tributaries include Purna, Wardha, Pranhita (large). Compare with Narmada (shorter, west flow), Krishna (1400 km), Mahanadi (860 km) to emphasize length and basin size. Discuss its seasonal flow and economic role in agriculture.
5. Rift valley river? (PDF p.24, NCERT Q1(v))
Answer: The Tapi flows through a rift valley, rising in Satpura ranges in Betul, Madhya Pradesh, parallel to Narmada but shorter. Its basin covers Madhya Pradesh, Gujarat, Maharashtra. Unlike east-flowing rivers like Mahanadi, Tungabhadra, Krishna, Tapi forms estuaries, not deltas. Explain rift valley formation due to faulting, coastal plains' narrowness leading to short west-flowing rivers. Highlight differences in courses and basins for detailed comparison.
6. Water divide? (PDF p.24, NCERT Q2(i))
Answer: A water divide is an elevated area like a mountain or upland separating two drainage basins, directing stream flow in opposite directions. Example: Ambala divide between Indus and Ganga systems. It determines river courses and basins. In India, Western Ghats divide east/west Peninsular rivers. Discuss role in hydrology, with figures like 3.1, and impacts on agriculture/settlements in basins.
7. Largest basin India? (PDF p.24, NCERT Q2(ii))
Answer: The Ganga has the largest basin in India, over 2500 km long, covering states like Uttar Pradesh, Bihar, West Bengal. Formed by Himalayan and Peninsular tributaries, it supports dense population and agriculture. Compare with Indus (international) or Godavari (largest Peninsular). Explain basin formation from alluvium and economic significance like irrigation.
8. Indus/Ganga origin? (PDF p.24, NCERT Q2(iii))
Answer: The Indus originates in Tibet near Lake Mansarowar, flowing west into India in Ladakh. The Ganga originates from Gangotri Glacier in Uttarakhand as Bhagirathi, joining Alaknanda at Devaprayag. Both are Himalayan perennial rivers. Discuss their paths: Indus to Arabian Sea, Ganga to Bay of Bengal, with gorges and basins. Highlight snow/rain sources for perennial flow.
9. Ganga headstreams? (PDF p.24, NCERT Q2(iv))
Answer: The two headstreams of the Ganga are Bhagirathi (from Gangotri Glacier) and Alaknanda. They meet at Devaprayag in Uttarakhand to form the Ganga. This confluence is sacred and marks the river's start. Explain glacial origins, emergence at Haridwar onto plains, and addition of tributaries like Yamuna. Discuss cultural/economic importance.
10. Brahmaputra less silt Tibet? (PDF p.24, NCERT Q2(v))
Answer: The Brahmaputra in its Tibetan part has less silt despite a longer course because it flows through a cold and dry area with smaller water volume. In India, high rainfall increases water and silt, leading to braided channels and floods. Known as Tsang Po in Tibet. Compare with Indian section: braided, islands like Majuli, devastation in Assam/Bangladesh. Explain silt deposition raising riverbed.
11. Rift trough rivers? (PDF p.24, NCERT Q2(vi))
Answer: The Narmada and Tapi are two Peninsular rivers that flow through troughs or rift valleys. Narmada rises at Amarkantak, flows west with features like Marble rocks; Tapi rises in Satpura, parallel to Narmada. Both form estuaries, not deltas. Discuss faulting origin, short tributaries, basins (MP/Gujarat/Maharashtra). Contrast with east-flowing delta-forming rivers.
12. Economic benefits rivers/lakes? (PDF p.24, NCERT Q2(vii))
Answer: Rivers provide water for irrigation, navigation, hydro-power, essential for agriculture (major livelihood in India). Lakes regulate flow, prevent floods, maintain dry-season water, generate hydel power, moderate climate, support ecosystems, enhance beauty/tourism/recreation. Examples: Ganga irrigation, Shivasamudram hydel, Dal tourism. Discuss settlements on banks, pollution threats, conservation like NRCP.
13. Group lakes natural/human. (PDF p.24, NCERT Q3)
Answer: Natural lakes: (a) Wular (tectonic), (b) Dal (freshwater), (c) Nainital (glacial), (d) Bhimtal (glacial), (f) Loktak (freshwater), (g) Barapani (freshwater), (h) Chilika (lagoon), (i) Sambhar (salt), (l) Pulicat (lagoon). Human-created: (e) Gobind Sagar (dam), (j) Rana Pratap Sagar (dam), (k) Nizam Sagar (dam), (m) Nagarjuna Sagar (dam), (n) Hirakund (dam). Explain formations: natural from glaciers/rivers/wind, human from damming for hydel/irrigation. Discuss examples' locations and uses.
14. Himalayan/Peninsular difference. (PDF p.24, NCERT Q4)
Answer: Himalayan rivers (Indus, Ganga, Brahmaputra) are perennial from rain/snow, with long courses, gorges in upper, meanders/deltas in lower, large basins. Peninsular (Godavari, Krishna) are seasonal rainfall-dependent, shorter/shallower, originate highlands/Ghats, form deltas (east) or estuaries (west), smaller basins. Himalayan: erosional/depositional intensive, flood-prone; Peninsular: less silt, no gorges. Discuss relief control, examples, economic contrasts like perennial irrigation vs seasonal.
15. East/west Peninsular rivers compare. (PDF p.24, NCERT Q5)
Answer: East-flowing Peninsular rivers like Mahanadi, Godavari, Krishna, Kaveri originate Western Ghats, flow to Bay of Bengal, form deltas, longer with larger basins. West-flowing like Narmada, Tapi originate central highlands, flow to Arabian Sea through rift valleys, form estuaries, shorter due to narrow coastal plains. East: seasonal but more water; West: even shorter flow. Discuss divide (Western Ghats), examples' lengths/basins, economic uses like deltas for agriculture.
16. Rivers economy importance? (PDF p.24, NCERT Q6)
Answer: Rivers are crucial for India's economy as they provide water for irrigation, supporting agriculture (major livelihood), navigation for transport, hydro-power for energy. Settlements/cities developed on banks since ancient times, e.g., Delhi on Yamuna. They enable hydel projects like Bhakra Nangal. However, floods/pollution pose challenges; conservation like Namami Gange ensures sustainability. Discuss complementarity with other features, role in population density.
17. Brahmaputra tributaries. (PDF p.20)
Answer: The Brahmaputra, as Dihang in India, is joined by tributaries like Dibang and Lohit in Arunachal Pradesh, forming the main river in Assam. These contribute to its large volume and silt in rainy season. The river's braided nature and islands result from this. Compare with Tibetan course (less tributaries/silt). Discuss flood impacts in Assam/Bangladesh, economic benefits like soil enrichment.
18. Godavari basin states. (PDF p.21)
Answer: The Godavari basin covers Maharashtra (about 50% area), Madhya Pradesh, Odisha, and Andhra Pradesh. As largest Peninsular basin, it supports agriculture across these states. Tributaries like Pranhita enhance flow. Discuss seasonal nature, delta formation, comparison with other basins like Krishna. Highlight role as Dakshin Ganga in southern economy.
19. Lakes formation examples. (PDF p.22)
Answer: Glacial lakes form when glaciers dig basins filled by snowmelt, e.g., Nainital, Bhimtal in Himalayas. Tectonic like Wular from earth's movements. Oxbow from meandering river cut-offs in floodplains. Lagoons from coastal spits/bars, e.g., Chilika. Artificial from dams, e.g., Gobind Sagar. Discuss seasonal inland like Sambhar. Explain importance in tourism/ecosystem, with examples' locations.
20. NRCP details. (PDF p.23)
Answer: The National River Conservation Plan (NRCP) was launched in 1995, expanding the Ganga Action Plan (1985) to other rivers. Objective: Improve water quality of major rivers through pollution abatement works like treating sewage/effluents. It addresses growing demands reducing river volume/self-cleansing. Discuss impacts on health, examples like Ganga assimilation failure due to urbanization. Highlight flagship status and ongoing relevance.
Practice Tip: 2M: 2min; 4M: 5min; 8M: 12min; use PDF maps/figures.
