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 March 2026. Share your views and suggestions in the comment box or at manas.srivastava@indianexpress.comWith reference to the new technology called VitalID, consider the following statements:1. It uses the vibrations generated by our breathing and heartbeats for logging into apps and websites.3. It has been designed primarily for extended reality environments.Which of the statements given above is/are correct?(a) 1 and 2 only(b) 3 only(c) 2 and 3 only(d) 1, 2 and 3Relevance: Topics like VitalID reflect the growing importance of emerging authentication technologies. The emerging technologies are important for UPSC prelims. Aspirants should keep a track for them.Explanation— A new technology called VitalID promises to revolutionise how we log into different apps and websites, especially those offering an immersive digital experience. Instead of entering passwords or scanning our faces, we can use the subtle movements generated by our own bodies to log in. The study was conducted in collaboration with researchers from the New Jersey Institute of Technology, Temple University, and Texas A&M University.— VitalID technology uses the vibrations generated by our breathing and heartbeats. These subtle movements travel through the neck and into our skulls. Because every person’s bone structure and tissue are slightly different, these patterns are unique— much like fingerprints. Hence, statement 1 is correct.Story continues below this ad— It does not require any additional hardware. Instead, it relies on motion sensors already built into many modern headsets. Hence, statement 2 is correct.— The system was introduced at the 2025 ACM Conference on Computer and Communications Security and is designed primarily for extended reality environments. Hence, statement 3 is correct.— Extended reality, abbreviated as XR, comprises virtual reality, augmented reality, and mixed reality technologies. XR technologies combine the physical world with digital elements. XR technologies are mostly used in gaming platforms such as Viture, Meta Quest, and Oculus Rift. However, the use of XR technologies has been increasing.Therefore, option (d) is the correct answer.QUESTION 2With reference to the Low Earth Orbit (LEO), consider the following statements:1. It is between 400 to 2,000 km altitude.2. It allows for high-latency communication than Medium Earth Orbit.Story continues below this ad3. In India, the Satellite internet is based on satellites placed only in LEO.How many of the statements given above are correct?(a) Only one(b) Only two(c) All three(d) NoneRelevance: Aspirants can expect questions testing conceptual clarity on types of satellite orbits (LEO, MEO, GEO) and their characteristics such as altitude and latency. The focus on satellite internet and space sector reforms makes it important for prelims.Explanation— LEO satellites orbit close to Earth, with altitudes ranging from 400 to 2,000 kilometres. Their proximity enables low-latency communication, making them excellent for internet services. Hence, statement 1 is correct.— MEO satellites operate at altitudes ranging from 8,000 to 20,000 km. They cover a broader area than LEO satellites and have slightly higher latency. Hence, statement 2 is not correct.Story continues below this ad— Satellite internet is an internet service delivered by satellites in geostationary or non-geostationary orbits (GSO or NGSO). India is shifting its satellite internet landscape from GEO (Geostationary Earth Orbit) satellites to LEO (Low Earth Orbit) and MEO (Medium Earth Orbit) systems. This transformation will provide quicker and more dependable internet connectivity across the country. Hence, statement 3 is not correct.— LEO satellites are used in satellite internet ventures in India, including those of Bharti Airtel (via OneWeb) and Reliance Jio (via JioSpaceFiber).Therefore, option (a) is the correct answer.(Source: http://www.pib.gov.in)QUESTION 3With reference to the Scramjet engine, consider the following statements:1. The Scramjet engine designed by ISRO uses Hydrogen as fuel and the Oxygen from the atmospheric air as the oxidiser.Story continues below this ad2. India has successfully conducted an active cooled scramjet combustor ground test.3. It efficiently operates at hypersonic speeds and allows supersonic combustion.Which of the statements given above are correct?(a) 1 and 3 only(b) 2 and 3 only(c) 1 and 2 only(d) 1, 2 and 3Relevance: It is important for understanding next-generation launch vehicles and missile technology. Questions can be framed testing basic working principles of emerging technologies. Aspirants should be aware of such technologies.Explanation— Last year, the Defence Research and Development Organisation (DRDO) demonstrated the scramjet combustor ground test for 120 seconds for the first time in India. The Ministry of Defence (MoD) has called it a crucial milestone in developing next-generation hypersonic missiles. Hence, statement 2 is correct.Story continues below this ad— The Scramjet engine designed by ISRO uses Hydrogen as fuel and the Oxygen from the atmospheric air as the oxidiser. Hence, statement 1 is correct.— Ramjets work most efficiently at supersonic speeds around Mach 3, three times the speed of sound. However, the ramjet efficiency reduces once the vehicle reaches hypersonic speeds – above Mach 5. This is where the Supersonic Combustion Ramjet or Scramjet engine comes in. It efficiently operates at hypersonic speeds and allows supersonic combustion. Hence, statement 3 is correct.— The fundamental change in a scramjet is that the air does not slow down in its combustion chamber but stays supersonic throughout the engine. This makes the design, development and operation of the scramjet far more challenging.Therefore, option (d) is the correct answer.QUESTION 4The “Earthset” is an event, which refer to:(a) When Earth dips below the lunar horizon(b) When the Sun sets as seen from Earth(c) When the Moon disappears below the Earth’s horizonStory continues below this ad(d) When a satellite moves out of Earth’s gravitational fieldRelevance: It is linked to space exploration and observational astronomy. UPSC can ask conceptual questions on recent scientific terms, space phenomena, and new technologies.Explanation— The crew on Nasa’s Artemis II mission have managed to take a picture showing Earth slowly disappearing behind the Moon—an event they call “Earthset”. The photograph, taken on Flight Day 6 of the mission, offers a rare perspective that few humans have ever seen.— “Earthset” is a historic photograph taken on April 6, 2026, by the Artemis II crew, showing Earth dipping below the lunar horizon as seen from their spacecraft.Story continues below this ad— The Artemis II crew, Nasa astronauts Reid Wiseman, Victor Glover, and Christina Koch, along with Canadian astronaut Jeremy Hansen, named the moment “Earthset” in reference to the famous “Earthrise” photograph taken during the Apollo 8 mission in 1968.Therefore, option (a) is the correct answer.QUESTION 5With reference to the Graphene, which of the following statements is/are correct?1. It is a one-atom-thick layer of carbon atoms arranged in a hexagonal lattice.2. It is not electrically conductive.3. It has very low mechanical strength and is easily breakable.How many of the statements given above are correct?(a) Only one(b) Only two(c) All three(d) NoneRelevance: It is significant in nanotechnology and advanced material. It is often in news due to its applications in electronics, energy storage, and defence, making it relevant for current affairs-based questions. Aspirants must be aware of the basic concepts underlying the technology.Explanation— Graphene is a one-atom-thick layer of carbon atoms arranged in a hexagonal lattice. Hence, statement 1 is correct.— It is the building-block of Graphite, but graphene is a remarkable substance on its own with a multitude of astonishing properties.— It is the thinnest, most electrically and thermally conductive material in the world, while also being flexible, transparent and incredibly strong. Hence, statement 2 is not correct.— Graphene is also known as a wonder material due to its vast potential in the energy and medical world. Graphene is extremely strong, even stronger than steel by weight. Hence, statement 3 is not correct.Therefore, option (a) is the correct answerPrevious Daily Subject-Wise-QuizDaily Subject-wise quiz — History, Culture, and Social Issues (Week 152)Daily subject-wise quiz — Polity and Governance (Week 157)Daily subject-wise quiz — Science and Technology (Week 156)Daily subject-wise quiz — Economy (Week 156)Daily subject-wise quiz — Environment and Geography (Week 156)Daily subject-wise quiz – International Relations (Week 156)Subscribe to our UPSC newsletter and stay updated with the news cues from the past week.Stay updated with the latest UPSC articles by joining our Telegram channel – IndianExpress UPSC Hub, and follow us on Instagram and X.