UPSC Essentials: Subject-wise Quizzes for Static Syllabus

UPSC Essentials brings to you its initiative of subject-wise quizzes. These quizzes are designed to help you revise some of the most important topics from the static part of the syllabus. Attempt today’s subject quiz on Science and Technology to check your progress. 🚨 Click Here to read the UPSC Essentials magazine for July 2026 . Share your views and suggestions in the comment box or at manas.srivastava@ indianexpress.com 🚨 With reference to the Thirty Meter Telescope (TMT), consider the following statements: 1. The primary mirror of the Thirty Meter Telescope is a single monolithic mirror measuring 30 metres in diameter. 2. The Thirty Meter Telescope is designed to observe only in the visible spectrum of light. 3. India is a partner in the Thirty Meter Telescope project. How many of the statements given above are correct? (a) Only one (b) Only two (c) All three (d) None Relevance: The Thirty Meter Telescope (TMT) is a major international astronomy project involving India’s scientific and technological participation. UPSC can ask questions on large-scale scientific missions, international collaborations, and advanced observational facilities in the Science and Technology section. Explanation — The Spanish government in partnership with the European Investment Bank (EIB) has announced to mobilize an estimated up to one billion Euro towards building the Thirty Metre Telescope (TMT) — the world’s largest optical telescope . — The TMT International Observatory is likely to be built at the Roque de los Muchachos Observatory in La Palma, Spain. — India is one of the member countries in the international consortium comprising the US, Canada, Japan and China. At the time when India joined this consortium in September, 2014, India had committed to contribute 10 per cent of the costs ( approximately Rs. 13,00 crore). Department of Science and Technology would be the nodal agency and will be co-ordinated by the Department of Atomic Energy. What will India contribute? — India is committed to provide ground and polished mirror segments, 84 in number, required for the large primary mirror of the telescope. India will also manufacture all the precision actuators, edge sensors and Segment Support Assembly (SSA). Hence, statement 3 is correct. — This is a complex opto-mechanical sub-assemblies that will hold together and control the alignment of each of the 492 hexagonal mirrors that will form the 30-metre primary mirror. 100 SSA segments and 80 mirrors, designed to be placed along the primary mirror’s periphery, will be manufactured in India. Hence, statement 1 is not correct. — The TMT is designed to observe the universe across the near-ultraviolet, visible, and mid-infrared wavelengths, not just the visible spectrum. Hence, statement 2 is not correct. Therefore, option (a) is the correct answer. The Blue Ghost and Resilience rovers are associated with: a) Development of reusable launch vehicles for interplanetary travel (b) Deployment of a satellite constellation for deep-space communication (c) Sample return missions from the asteroid belt (d) Commercial lunar exploration and technology demonstration missions Relevance: Recent developments in lunar exploration and the growing role of private players in space missions have brought renewed focus to commercial space activities. UPSC can ask questions on current space missions, emerging technologies, and international collaborations. Explanation — A SpaceX rocket launched a year ago is set to crash into the Moon this week. The Falcon 9 rocket is predicted to slam onto the Moon’s surface . The rocket has been hovering aimlessly high above Earth’s orbit for more than 1.5 years. — The Falcon 9 w as launched in January 2025 with two private robotic lunar landers as cargo. SpaceX Falcon 9 rockets are known for reusing the first stage, while the upper stages are typically single-use. In typical SpaceX launches, they deorbit the rocket stages and guide them back to a controlled area for recovery and destruction. The Falcon 9 does not have a similar case; it used up all the upper-stage fuel to get to the deployment point of the rovers. — The rocket was carrying two rovers: Blue Ghost and Resilience. Blue Ghost landed successfully and carried on with its historic mission, and Resilience crashed while trying to touch down. The Falcon 9 upper stage was not the first rocket body to strike the Moon. Several Saturn V third stages from Nasa’s Apollo missions were deliberately crashed into the lunar surface for scientific research. On March 4, 2022, a mystery rocket stage slammed into the Moon, creating an unusual double crater. Scientists later identified the impactor as the upper stage of China’s Long March 3C rocket, which launched the uncrewed Chang’e 5-T1 lunar mission in October 2014. Therefore, option (d) is the correct answer. With reference to quantum computers, consider the following statements: 1. Unlike classical computers, quantum computers use qubits that can exist only in either the 0 or the 1 state at a given time. 2. A photonic quantum computer uses individual light particles as qubits to encode and process information. Which of the statements given above is/are correct? (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2 Relevance: Quantum computing is an emerging technology with applications in computing, cryptography, and scientific research. UPSC has increasingly focused on frontier technologies such as quantum computing, artificial intelligence, and semiconductors in the Science and Technology section. Explanation — A quantum computer differs from a normal or classical computer mainly in the way it is built and operates. While the latter uses bits (basic unit of classical information) that are either 0 or 1, a quantum computer uses qubits (fundamental unit of quantum information) that can be both at the same time. Hence, statement 1 is not correct. — A photonic quantum computer uses individual light particles, or photons, as qubits to encode and process information. Hence, statement 2 is correct. Therefore, option (a) is the correct answer. Consider the following statements: 1. Turbulence is an irregular motion of the air resulting from circular whirls of air. 2. It is caused by factors such as surface heating, friction, and obstacles that disrupt the smooth flow of air, leading to the formation of eddies. Which one of the following is correct in respect of the above statements? (a) Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation for Statement 1. (b) Both Statement 1 and Statement 2 are correct and Statement 2 is not the correct explanation for Statement 1. (c) Statement 1 is correct but Statement 2 is incorrect. (d) Statement 1 is incorrect but Statement 2 is correct. Relevance: Atmospheric processes and weather phenomena are recurring themes in UPSC Science and Technology and Geography. Understanding concepts such as turbulence, air circulation, and factors influencing weather is important for interpreting current developments related to aviation, climate, and meteorology. Explanation — An Air India aircraft encountered severe mid-flight turbulence on Tuesday while flying from Phuket to Delhi, experiencing a sudden drop of about 300 feet and resulting in injuries to some of the passengers and cabin crew members . — Turbulence is an irregular motion of the air resulting from circular whirls of air, or eddies, and vertical air currents—updrafts and downdrafts. Its severity can range from a few minor bumps during the flight to the aircraft tossing around with rapid and harsh changes in altitude, which can lead to injuries to those on board and also result in structural damage to the plane in rare cases. Hence, statements 1 and 2 are correct. — Turbulence is a routine occurrence with scores of flights encountering it to varying degrees on a daily basis all over the world. Some of it may be near the ground, when strong winds around the airport can cause turbulence as aircraft take off or land, or at higher altitudes, where an updraft or downward flow of air in storm clouds can trigger some turbulence as planes fly through or near them. Turbulence also occurs on the edges of jet streams — strong, fast, and narrow air currents that circle the globe. Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation for Statement 1. Therefore, option (a) is the correct answer. Consider the following statements: 1. A heart attack occurs when blood flow to a part of the heart muscle is blocked. 2. A cardiac arrest is due to an electrical disorder causing the heart to stop beating effectively. Which of the statements given above is/are correct? (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2 Relevance: Health-related current affairs, particularly those involving lifestyle diseases, medical emergencies, and advances in healthcare, are increasingly important for prelims. UPSC can ask conceptual questions distinguishing related medical conditions and biological processes. Explanation — A heart attack occurs when blood flow to a part of the heart muscle is blocked. “A heart attack occurs when the flow of blood to a section of the heart is blocked and this results in damage to the heart muscle. Hence, statement 1 is correct. — A cardiac arrest, however, is an electrical problem. “A cardiac arrest is different since it is due to an electrical disorder causing the heart to stop beating effectively and thus cutting off the supply of blood to the brain and to other organs.” Hence, statement 2 is correct. — Heart failure, on the other hand, is usually a long-term condition. “Heart failure is a chronic condition in which the heart becomes either too weak or too stiff to pump blood efficiently.” Therefore, option (c) is the correct answer. Daily Subject-wise quiz — History, Culture, and Social Issues (Week 159) Daily subject-wise quiz — Polity and Governance (Week 174) Daily subject-wise quiz — Science and Technology (Week 173) Daily subject-wise quiz — Economy (Week 173) Daily subject-wise quiz — Environment and Geography (Week 173) Daily subject-wise quiz – International Relations (Week 173) Subscribe to our UPSC newsletter and stay updated with the news cues from the past week. 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