Question map
With reference to Agni-IV Missile, which of the following statements is/are correct? 1. It is a surface-to-surface missile. 2. It is fuelled by liquid propellant only. 3. It can deliver one-tonne nuclear warheads about 7500 km away. Select the correct answer using the code given below.
Explanation
The Agni-IV is indeed a surface-to-surface missile[2], making statement 1 correct.
Statement 2 is incorrect. The Agni-IV is a two-stage, solid-fueled[4] missile, not liquid-fueled[3]. It uses solid propellant for both stages, contrary to the claim that it is fuelled by liquid propellant only.
Statement 3 is also incorrect. The maximum range of the[6] Agni-IV missile is [5]3,000-4,000 km, not 7,500 km as stated. While the missile can carry a 1,000 kg (one-tonne) nuclear[8] warhead, the range specification in statement 3 is significantly overstated—almost double the actual capability.
Therefore, only statement 1 is correct, making option A the right answer.
Sources- [1] https://en.wikipedia.org/wiki/Agni-IV
- [2] https://missilethreat.csis.org/missile/agni-4/
- [3] https://missilethreat.csis.org/missile/agni-4/
- [4] https://missilethreat.csis.org/missile/agni-4/
- [6] https://missilethreat.csis.org/missile/agni-4/
- [7] https://missilethreat.csis.org/missile/agni-4/
- [8] https://missilethreat.csis.org/missile/agni-4/
PROVENANCE & STUDY PATTERN
Full viewThis is a classic 'Spec-Swap' trap. UPSC took the Agni-IV missile but swapped its features with Prithvi (liquid fuel) and an exaggerated ICBM range. You don't need to be a DRDO scientist, but you must know the 'Big 3' specs (Range, Fuel, Type) for India's flagship strategic assets.
This question can be broken into the following sub-statements. Tap a statement sentence to jump into its detailed analysis.
- Statement 1: Is the Agni-IV missile a surface-to-surface missile?
- Statement 2: Is the Agni-IV missile fuelled only by liquid propellant?
- Statement 3: Is the maximum range of the Agni-IV missile approximately 7500 kilometers?
- Statement 4: Can the Agni-IV missile deliver a one-tonne (1000 kg) nuclear warhead?
- The cited text on the Agni-IV page explicitly describes the missile as "surface-to-surface."
- The Wikipedia entry's citations include news headlines calling it a "surface-to-surface Agni-IV missile."
- The CSIS Missile Threat entry quotes DRDO describing the Agni-4 as a "sophisticated surface-to-surface missile."
- The profile classifies Agni-IV as an intermediate-range ballistic missile, consistent with surface-launched ballistic systems.
Mentions Dr. A.P.J. Abdul Kalam as 'Missile Man' tied to development of India's missile programme, indicating a national programme that produced named missiles.
A student could use this to locate the Agni series within India's missile programme records (e.g., DRDO/Defence sources) to see their class and launch/target type.
Refers to specific missiles (Prithvi) being inducted into the army, showing India deploys missiles with service-specific roles (army, navy, air force).
A student could check whether Agni-IV is listed as inducted to a service branch (army/strategic forces) which commonly operate surface-launched, surface-to-surface ballistic missiles.
Notes India joined the Missile Technology Control Regime (MTCR), linking India to international categorizations and controls of missile types and technologies.
A student could consult MTCR/related lists or technical descriptions used by export-control regimes to see how Agni-class missiles are categorised (e.g., surface-to-surface ballistic).
Discusses ballistic missiles in the context of strategic arms control, providing a definitional context that distinguishes ballistic missiles as a class of strategic, usually surface-launched weapons.
A student could use that general definition (ballistic missiles as strategic weapons discussed in arms-control texts) to infer that an 'Agni' named in India's strategic programme might be a ballistic surface-launched missile and then verify platform/trajectory details.
Lists 'missiles' among objects affected by the Coriolis effect, implicitly treating missiles as projectiles with defined trajectories subject to Earth-relative forces.
A student could use this general physics point to distinguish missile flight profiles (ballistic arc from surface launch vs. air-launched/ship-launched) and then check Agni-IV's launch platform to infer surface-to-surface role.
- Explicitly states the claim in question.
- Directly answers that Agni-IV is fuelled by liquid propellant only.
- Directly contradicts the statement by describing the missile's propellant type.
- Provides a clear technical description: two-stage, solid-fueled.
- Summarizes propulsion as 'Two-stage solid propellant', reinforcing the refutation.
- Gives concise specification that directly addresses fuel type.
Lists production of 'solid, liquid, cryogenic and semi-cryogenic propellants' as distinct classes for space/national-security launch systems, showing multiple propellant types are used in rocket systems.
A student could use this rule plus basic knowledge that ballistic/launch vehicles can use any of these classes to infer that one should check which class Agni‑IV belongs to rather than assume 'only liquid'.
Describes that combustion processes can yield gas and liquid fuels and that fuels exist in multiple phases (solid, liquid, gas).
Combine this with the propellant-class list to motivate checking whether Agni‑IV uses solid, liquid or other-phase propellant.
Discusses kerosene (a liquid fuel) being a distinct category of fuel used historically, implying liquid fuels are one of several fuel types in practical use.
Use this to recognize that the presence of liquid fuels in some systems does not imply all systems (e.g., missiles) are liquid‑fuelled—so verify Agni‑IV's specific fuel type.
Explains natural gas as a fuel and notes diversity of fuel applications, reinforcing that fuels come in different forms for different uses.
A student could note the diversity and therefore check technical specifications of Agni‑IV to determine whether it uses liquid, solid, or other propellant.
- Explicitly states a numeric maximum range for the Agni-IV that is far lower than 7,500 km.
- Directly contradicts the 7,500 km figure by giving 4,000 km as the maximum.
- Provides a summarized range band for Agni-IV (3,000–4,000 km), which is much less than 7,500 km.
- Reinforces other sources that place Agni-IV in the IRBM/intermediate-range category, not near 7,500 km.
Discusses arms control and treaties (ABM, SALT, START) that distinguish strategic ballistic missile classes, implying that missile ranges are politically salient and categorized.
A student could use these treaty-based classes (e.g., intermediate vs. intercontinental) plus a world map to judge whether ~7500 km falls into an ICBM or intermediate category and thus whether Agni-IV is likely to be in that class.
Gives a concrete India–China western sector land distance (about 2152 km), supplying a regional distance scale for assessing what ranges are needed for regional strike capability.
Combine this regional distance with a map to see which countries/regions a 7,500 km missile from India would reach versus shorter-range missiles like those covering ~2,000–3,000 km.
Provides an example contrasting communication distances (500 km vs. 5,000 km) to illustrate orders of magnitude for long-distance capability.
Use the same order-of-magnitude thinking to compare 7,500 km with familiar long distances (e.g., continental spans) to assess plausibility of labeling Agni-IV as covering that range.
Lists Indian rocket/satellite launches and launch sites, indicating India's indigenous long‑range rocketry and space-launch experience.
A student could combine evidence of Indian launch capability with a map and basic rocket-range knowledge to infer whether India had the technological base to develop a ~7,500 km-range missile by the dates mentioned.
- The CSIS fact sheet lists the missile payload capacity as 1,000 kg.
- The same entry identifies the warhead type as nuclear or conventional, implying a 1,000 kg nuclear warhead is compatible.
- The text explicitly states the missile's nuclear payload estimate as 1,000 kg.
- This directly supports that Agni-IV can carry a one-tonne nuclear warhead.
India's nuclear doctrine emphasises 'credible minimum deterrent' and development of retaliatory nuclear capabilities, implying India fields delivery systems (missiles) as part of that deterrent.
A student could infer India develops ballistic missiles with sufficient payloads and then check Agni-IV technical specs (range/payload) from missile data to evaluate the 1000 kg claim.
Restates India's commitment to credible minimum deterrence and 'no first use', which implies reliance on survivable and effective nuclear delivery platforms (including medium/long‑range missiles).
Use this rationale to narrow attention to India's Agni series as likely candidates for nuclear delivery and then consult their declared payload capacities.
Mentions induction of missiles (Prithvi I) and modernisation of defence/space tech, showing India has an active missile development and testing program.
Combine this pattern with open-source missile family information (Agni series progression) to assess probable payload growth and whether 1000 kg is plausible for Agni-IV.
Discussion of arms control and the role of ballistic missiles in nuclear attack/defence highlights that ballistic missiles are standard means to deliver nuclear warheads and that payload and defensive constraints matter strategically.
A student could use this to justify comparing Agni‑IV's reported missile class (ballistic) with typical payloads for similar-range ballistic missiles worldwide to judge feasibility of a 1000 kg warhead.
- [THE VERDICT]: Trap. The question looks factual but relies on detecting exaggerated numbers (7500 km) and obsolete tech (liquid fuel for modern strategic missiles).
- [THE CONCEPTUAL TRIGGER]: Science & Tech > Defence > IGMDP (Integrated Guided Missile Development Programme) & Strategic Forces Command assets.
- [THE HORIZONTAL EXPANSION]: Memorize the Agni Ladder: Agni-1 (700km, Solid), Agni-2 (2000km, Solid), Agni-3 (3000km, Solid), Agni-4 (4000km, Solid), Agni-5 (5000km+, Solid, Canisterised). Contrast with Prithvi (Liquid, Short Range) and BrahMos (Ramjet, Cruise).
- [THE STRATEGIC METACOGNITION]: Never read missile news in isolation. Always update a single 'Master Table' with columns: Name, Type (Ballistic/Cruise), Range, Fuel, and Special Feature (e.g., Canisterised, MIRV). If a statement violates the trend of that table (e.g., Agni series is solid-fueled for quick reaction), mark it wrong.
Reference [1] discusses ballistic missiles in the context of the ABM Treaty, which frames how ballistic missile deployment and defensive shields are regulated.
Understanding what constitutes a ballistic missile and how arms-control treaties (e.g., ABM, SALT, START) treat them is high-yield for UPSC GS and security topics; it links defence technology to international law and diplomacy. Master by mapping definitions (ballistic vs. cruise, offensive vs. defensive), treaty names/years, and implications for national strategy—use past UPSC questions and official treaty summaries for practice.
- Contemporary World Politics, Textbook in political science for Class XII (NCERT 2025 ed.) > Chapter 5: Security in the Contemporary World > Security in the Contemporary World 69 > p. 69
References [2] and [6] mention Prithvi's induction and Abdul Kalam's role in India's missile development, highlighting India's indigenous missile efforts.
Familiarity with India’s missile development history, key systems (e.g., Prithvi, Agni family contextually), and leading personalities is repeatedly tested in polity/defence/modern history mains and prelims. Prepare by creating a timeline of missile tests/inductions and biographies of key scientists; relate to defence modernisation and doctrinal changes.
- Rajiv Ahir. A Brief History of Modern India (2019 ed.). SPECTRUM. > Chapter 39: After Nehru... > Panchayati Raj and Nagarpalika Acts > p. 745
- Exploring Society:India and Beyond. Social Science-Class VI . NCERT(Revised ed 2025) > Chapter 10: Grassroots Democracy — Part 1: Governance > Dr. A.P.J. Abdul Kalam > p. 158
Reference [3] references India joining MTCR and Wassenaar, which are directly relevant to missile and related technology proliferation.
Comprehending multilateral export-control regimes is important for questions on non-proliferation, defence procurement, and foreign policy. Learn membership, objectives, and implications for technology transfer; link to case studies (India’s accession) to answer policy-analysis questions effectively.
- Rajiv Ahir. A Brief History of Modern India (2019 ed.). SPECTRUM. > Chapter 39: After Nehru... > Foreign Relations > p. 795
The statement asks about missile fuel type; one reference lists major propellant categories used in space/defence programmes.
Understanding the main propellant categories is high-yield for defence and technology questions in UPSC (missile classes, advantages/limitations, logistics). It connects to topics on indigenous manufacturing, supply chains, and platform capabilities, and lets candidates evaluate claims about a specific missile's fuel by comparing categories. Prepare by memorising categories, typical uses, and broad pros/cons rather than model-specific details.
- Indian Economy, Nitin Singhania .(ed 2nd 2021-22) > Chapter 14: Service Sector > 14.12 Indian Economy > p. 434
Liquid behaviour and pressure in containers are shown in the NCERT references; these fundamentals matter when considering liquid propellant handling and tank design.
Grasping basic liquid properties helps reason about practical issues of liquid-fuelled missiles (pressurisation, storage hazards, handling infrastructure) which often appear in integrated GS and technical-general knowledge questions. Revision should focus on core physics concepts (pressure, fluid behaviour) and their applied implications for fuel systems.
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 6: Pressure, Winds, Storms, and Cyclones > > p. 84
- Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 7: Particulate Nature of Matter > Keep the curiosity alive > p. 113
One reference lists production areas (propellants, composites, avionics) highlighting the industrial base needed for missile/space systems.
UPSC aspirants should link technology topics to industrial capacity and policy (domestic production of propellants, materials, avionics). Questions probe capability building and self-reliance; studying this helps answer questions on defence preparedness and Make-in-India initiatives. Focus preparation on mapping components-to-industries and policy implications.
- Indian Economy, Nitin Singhania .(ed 2nd 2021-22) > Chapter 14: Service Sector > 14.12 Indian Economy > p. 434
Reference [2] discusses arms control and explicitly mentions 'ballistic missiles' and the ABM Treaty, which frames international limits and debates around missile deployment and capabilities.
Understanding arms-control frameworks helps aspirants evaluate statements about missile capabilities in a policy context — e.g., how treaties affect deployment and perceived threats. This is high-yield for GS Paper II/International Relations and links to defence, strategic stability, and disarmament topics. Prepare by studying major treaties, their scope, and implications for missile programs.
- Contemporary World Politics, Textbook in political science for Class XII (NCERT 2025 ed.) > Chapter 5: Security in the Contemporary World > Security in the Contemporary World 69 > p. 69
Agni-Prime (Agni-P). It is the modern, canisterised replacement for the older Agni-1/2. Key feature: Maneuverable Reentry Vehicle (MaRV) and high accuracy, not just range. Also, watch out for 'Pralay' (quasi-ballistic, surface-to-surface).
The 'Agni-V Ceiling' Logic. In 2014 (and even now), Agni-V was India's crown jewel for long-range capability, touted as reaching ~5000-5500 km. If the pride of the nation is ~5000 km, how can Agni-IV (a lower number) be 7500 km? Statement 3 is logically impossible based on the hierarchy of names.
Link Fuel Type to Nuclear Doctrine (GS-2/GS-3). India has a 'No First Use' policy, meaning we must survive a first strike and retaliate quickly. Liquid-fueled missiles take hours to fuel and are dangerous to store loaded; Solid-fueled missiles (Agni series) are 'fire-and-forget' ready. This technical shift is a strategic necessity.