Q100. The Sardar Sarovar multipurpose dam is built on which river?
[RPF Constable, 7 March 2025]
(A) Tapi
(B) Mahi
(C) Narmada
(D) Godavari
Answer: C. Narmada
Explanation: Sardar Sarovar is a major project on the Narmada in Gujarat. It supports irrigation, water supply and hydroelectric generation. Its power and water benefits reach multiple regions, illustrating the integrated role of multipurpose river-valley projects.
Q99. Which alcohol is blended with petrol under India’s fuel-blending programme?
[MP Police Constable, 12 November 2025]
(A) Methanol only
(B) Ethanol
(C) Ethylene glycol
(D) Butanol only
Answer: B. Ethanol
Explanation: Ethanol is the alcohol widely used in India’s petrol-blending programme. It can be produced from suitable sugarcane, grain and other feedstocks. Blending creates an additional market for biomass-derived fuel while partially replacing conventional petrol components.
Q98. Which refinery has the greatest capacity among Barauni, Mathura, Trombay and Koyali in the cited comparison?
[BPSC 70th Combined Competitive Re-examination, 4 January 2025]
(A) Barauni
(B) Mathura
(C) Trombay
(D) Koyali
Answer: D. Koyali
Explanation: Koyali, also known as Gujarat Refinery, is a large petroleum refinery near Vadodara. The question compares the listed facilities, not all refineries in India. Refining transforms crude oil into petrol, diesel, LPG and numerous petrochemical inputs.
Q97. Which sequence best represents increasing coal rank through coalification?
[RRB JE CBT-II, 22 April 2025]
(A) Peat → lignite → bituminous → anthracite
(B) Anthracite → peat → lignite → bituminous
(C) Bituminous → anthracite → peat → lignite
(D) Lignite → peat → anthracite → bituminous
Answer: A. Peat → lignite → bituminous → anthracite
Explanation: Coalification progressively increases carbon concentration and usually energy density as buried organic matter experiences heat and pressure. Peat is an early precursor, followed by lignite and bituminous coal, with anthracite representing a high rank.
Q96. Which of these was NTPC’s first thermal power project?
[UPSSSC Stenographer, 16 November 2025]
(A) Singrauli
(B) Harduaganj
(C) Tanda
(D) Rihand
Answer: A. Singrauli
Explanation: Singrauli Super Thermal Power Station in Uttar Pradesh was NTPC’s first coal-based project. NTPC later developed large stations throughout the country. The location belongs to the Singrauli coal-power region of north-central India.
Q95. Which fuel is commonly called brown coal?
[RRB NTPC Undergraduate, 13 August 2025]
(A) Lignite
(B) Mica
(C) Copper
(D) Bauxite
Answer: A. Lignite
Explanation: Lignite is a brown, low-rank coal with relatively high moisture and lower heating value than many bituminous grades. India’s important lignite occurrences include Neyveli in Tamil Nadu, alongside deposits in Rajasthan and Gujarat.
Q94. In which early coalification material are plant remains often still recognisable?
[BPSC District Statistical Officer, 3 August 2025]
(A) Peat
(B) Bituminous coal
(C) Anthracite
(D) Coke
Answer: A. Peat
Explanation: Peat accumulates from partly decomposed vegetation, often in waterlogged conditions, and can retain visible plant structures. Burial and geological alteration over long periods create progressively higher coal ranks, including lignite, bituminous coal and anthracite.
Q93. Which of these is a non-conventional energy source?
[UPSC NDA-I General Ability Test, 13 April 2025]
(A) Petroleum
(B) Natural gas
(C) Tidal energy
(D) Coal
Answer: C. Tidal energy
Explanation: Tidal electricity captures periodic water movement associated with the Moon’s and Sun’s gravitational forces. Coal, petroleum and natural gas are conventional fossil fuels. Tidal technology is renewable although suitable coastal sites are geographically limited.
Q92. Which of the following is NOT a major oilfield in Gujarat?
[UPSC NDA-I General Ability Test, 13 April 2025]
(A) Ankleshwar
(B) Kosamba
(C) Mehsana
(D) Moran
Answer: D. Moran
Explanation: Moran is a petroleum-producing location in the Upper Assam Basin, not Gujarat. Ankleshwar, Kosamba and Mehsana are associated with Gujarat’s oil industry. Oilfields follow the distribution of suitable sedimentary rocks rather than state boundaries.
Q91. Salal Hydroelectric Project stands on which river?
[UPSC CDS-I General Knowledge, 13 April 2025]
(A) Chenab
(B) Jhelum
(C) Nubra
(D) Shyok
Answer: A. Chenab
Explanation: The Salal power station is built on the Chenab in Jammu and Kashmir. Its turbines exploit river flow and hydraulic head. Jhelum and Shyok are separate rivers and do not host this named hydropower project.
