प्रश्न यूपीएससी के हिंदी प्रश्नपत्र से · व्याख्या अभी अंग्रेज़ी में

Prelims · Science & technology · 32 questions

Defence, nuclear & energy technology

Every UPSC Prelims question on this topic, 2016–2026, newest first. Tap an option to check yourself; the answer and explanation open below it.

Asked in 9 of 11 years · most in 2026 (4)

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UPSC syllabus: “General Science.” Sub-topics in the detailed syllabus →

Prelims 2016 · Q46

X-Ray · Core #21 Easy

‘INS अस्त्रधारिणी’ का, जिसका हाल ही में समाचारों में उल्लेख हुआ था, निम्नलिखित में से कौन-सा सर्वोत्तम वर्णन है?

Read this question in English

Which one of the following is the best description of ‘INS Astradharini’, that was in the news recently?

(a) Amphibious warfare ship · (b) Nuclear-powered submarine · (c) Torpedo launch and recovery vessel · (d) Nuclear-powered aircraft carrier

उत्तर और व्याख्या · explanation in English

Answer: (c) टॉरपीडो प्रमोचन और पुनर्प्राप्ति (recovery) जलयान

INS Astradharini is an indigenously built Torpedo Launch and Recovery Vessel, commissioned into the Indian Navy on 6 October 2015 at Visakhapatnam. It is a small support vessel used to launch and recover torpedoes during underwater weapon trials, not a warship or submarine.

✓ (c) The Ministry of Defence release describes it as an indigenously built Torpedo Launch and Recovery Vessel, 50 m long, with a catamaran hull and a large deck with torpedo launchers.
✗ (a) An amphibious warfare ship carries and lands troops and vehicles; Astradharini is a 50 m trials-support vessel.
✗ (b) A nuclear-powered submarine is a combat vessel; Astradharini is a surface vessel for torpedo trials.
✗ (d) Astradharini is only 50 m long and is not an aircraft carrier of any kind.

Remember · INS Astradharini (commissioned 6 October 2015) is an indigenously built torpedo launch and recovery vessel of the Indian Navy.

Sources

PIB, Ministry of Defence: INS Astradharini Joins The Indian Navy (6 October 2015) ↗ “An indigenously built Torpedo Launch and Recovery Vessel ‘INS Astradharini’, was commissioned today, 06th October 2015 by Vice Admiral Satish Soni, Flag Officer Commanding Eastern Naval Command … It can operate at high sea states and has a large deck area with Torpedo Launchers for deploying and recovering various kinds of torpedos during the trials.”

Question and answer: UPSC's official GS Paper I (2016, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink ·

Prelims 2016 · Q79

Medium

भारत ‘अंतर्राष्ट्रीय ताप-नाभिकीय प्रायोगिक रिएक्टर (International Thermonuclear Experimental Reactor)’ का एक महत्त्वपूर्ण सदस्य है। यदि यह प्रयोग सफल हो जाता है, तो भारत का तात्कालिक लाभ क्या है?

Read this question in English

India is an important member of the 'International Thermonuclear Experimental Reactor'. If this experiment succeeds, what is the immediate advantage for India?

(a) It can use thorium in place of uranium for power generation · (b) It can attain a global role in satellite navigation · (c) It can drastically improve the efficiency of its fission reactors in power generation · (d) It can build fusion reactors for power generation

उत्तर और व्याख्या · explanation in English

Answer: (d) यह विद्युत् उत्पादन के लिए संलयन (फ्यूज़न) रिएक्टरों का निर्माण कर सकता है

ITER is an experiment to show that nuclear fusion, the joining of light atomic nuclei as in the Sun, can work at power-plant scale. Every ITER member shares the experimental results and intellectual property, so if it succeeds, India can build its own fusion reactors for power.

✓ (d) ITER is meant to prepare the way for future fusion power plants, and members share its results and intellectual property. Fusion power reactors are the natural next step for India.
✗ (a) Using thorium as fuel belongs to India's fission reactor programme; ITER is a fusion project and does not test thorium.
✗ (b) Satellite navigation depends on satellite systems (such as India's own navigation constellation), which have nothing to do with a fusion experiment.
✗ (c) Fusion is a different process from fission. A fusion success would not by itself make fission reactors more efficient.

Remember · ITER (in France; members China, EU, India, Japan, Korea, Russia, USA) tests nuclear fusion; the payoff is knowledge to build fusion power plants.

Sources

ITER Members (ITER Organization) ↗ · reference work “the ITER collaboration Members China, the European Union, India, Japan, Korea, Russia and the United States will share in the cost of project construction, operation and decommissioning, and also share in the experimental results and any intellectual property generated by the project.”
ITER in a few lines (ITER Organization) ↗ · reference work “ITER will bridge the gap between today's smaller-scale experimental fusion devices and the demonstration fusion power plants of the future.”

Question and answer: UPSC's official GS Paper I (2016, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink ·

The Syllabus X-Ray of this topic

2 of its 6 sub-topics are Core

2 Core · 0 High · 2 Steady · 2 Rare

Core #45Missiles & defence technology · 7 questions
Core #50Energy technology: batteries, hydrogen, fusion · 6 questions

The X-Ray ranks all 928 sub-topics of the UPSC syllabus by what UPSC has asked since 2016. The 60 Prelims Core sub-topics are behind 51% of Prelims questions.

See the whole X-Ray →

The same topic in Mains

Science & technology in everyday lifeGS 3 syllabus
Security forces & agenciesGS 3 syllabus

From the UPSC Blog

India’s Nuclear Doctrine: No First Use, Credible Minimum Deterrence and the Review Debate — UPSC Notes26 Sept 2026