Laser strums atoms trillions of times in search for better computers

✅ Statement I: Correct
Rare earth elements like europium, terbium, and yttrium are essential in flat TV screens and monitors due to their role in producing vibrant colors and enhancing display quality. ✅ Statement II: Correct
These elements exhibit phosphorescence—absorbing energy and slowly emitting light—which is key to their use in color reproduction and brightness in displays. Relationship:
Statement II explains why rare earth elements are crucial in displays, confirming the reason behind Statement I. Therefore, both statements are correct and related.

✅ Statement I: Correct
*GAGAN is an Indian SBAS developed by ISRO and AAI to enhance GPS accuracy and integrity, crucial for aviation safety.* ✅ Statement II: Correct
*It improves GPS reliability and accuracy, enabling better air traffic management and safer, efficient navigation.* ❌ Statement III: Incorrect
*GAGAN’s benefits extend beyond aviation to railways, roadways, maritime, agriculture, and disaster management.* Correct Answer: Only Statements I and II are correct.

Statement 1 is Correct: Mission Sudarshan Chakra is designed as a multi-domain security umbrella. It explicitly aims to enhance India's air defence, ballistic missile defence, and aerial offensive capabilities, acting as both a defensive shield and an offensive sword. Statement 2 is Correct: The mission integrates advanced technologies like AI, space-based sensors, and directed energy weapons to ensure rapid, precise, and powerful defence responses. This indigenous development (incorporating projects like Project Kusha) is specifically aimed at reinforcing India's strategic autonomy and self-reliance in the defence sector. Statement 3 is Correct: A major distinguishing feature of this initiative is its expanded scope. Announced as a 10-year national security initiative, a stated goal of the mission is to bring all public places (including hospitals, railways, and religious/cultural sites) under an expanded nationwide security shield by 2035, moving beyond the conventional protection of just military and strategic installations. Therefore, the correct option is A.

GPS, or Global Positioning System, is a satellite-based navigation system that provides geolocation and time information to a GPS receiver anywhere on or near the Earth. It has a wide range of applications. Statement 1 is correct. GPS is used in mobile phones for various purposes such as location tracking, navigation, and location-based services. Statement 2 is correct. GPS is used in banking operations for ATM location services and for time-stamping transactions, which is crucial for maintaining accurate records. Statement 3 is correct. GPS is used for time-stamping power system measurements, which is vital for grid stability and synchronization. Therefore, GPS technology can be used in all the three areas mentioned.

Statement 1 is Correct: Rare Earth Elements (REEs) are indispensable for modern technological innovations. Their unique magnetic, luminescent, and electrochemical properties make them critical for artificial intelligence hardware, robotics, space exploration, electric vehicles, and advanced defense systems. Statement 2 is Incorrect: While China dominates global REE mining, accounting for roughly 69% of global production, the second-largest producer is the United States, followed by Myanmar and Australia. India ranks much lower globally and is not the second-largest producer. Statement 3 is Correct: The Government of India officially launched the National Critical Mineral Mission (NCMM) in January 2025. The mission is a strategic blueprint designed to secure domestic and global supply chains, reduce import dependence, and establish a robust framework for self-reliance in critical minerals essential for clean energy and technology. Statement 4 is Incorrect: Rare Earth Elements are a set of 17 metallic elements, not 13. This group comprises the 15 lanthanides on the periodic table, along with scandium and yttrium, which share similar chemical properties and are typically found in the same ore deposits. Therefore, the correct option is A.

* Carbon fibres are highly valued for their unique properties like strength, lightness, and stiffness. They are widely used in the manufacturing of various components in automobiles and aircraft to reduce weight and improve performance.  * Carbon Fiber Recycling: While traditional carbon fibre recycling methods were limited, advancements are being made in this field. Here are some possibilities  1. Mechanical recycling - This process breaks down carbon fibres into smaller pieces for use in applications where their original form is not necessary.  2. Chemical recycling -This method dissolves the resin holding the fibres together, potentially allowing the extraction of reusable carbon fibres.  3. Thermal recycling - High temperatures are used to convert the resin into usable materials while recovering the carbon fibres.  * These recycling technologies are still evolving, but they offer a more sustainable approach to using carbon fibres. Hence, statement 2 is incorrect.

Statement 1 is Correct: The National Quantum Mission (NQM) aims to develop intermediate-scale quantum computers with 50 to 1000 physical qubits within 8 years. Specifically, it targets 50–100 physical qubits in 5 years and scales up to 50–1000 physical qubits in 8 years using platforms like superconducting and photonic technology. Statement 2 is Correct: The implementation of the mission explicitly includes the establishment of four Thematic Hubs (T-Hubs) in top academic and national R&D institutes across India. These hubs focus on distinct technology verticals: Quantum Computing (led by IISc Bengaluru), Quantum Communication (led by IIT Madras), Quantum Sensing & Metrology (led by IIT Bombay), and Quantum Materials & Devices (led by IIT Delhi). Therefore, both statements are correct.

Statement 1 is Incorrect: Black boxes are equipped with an Underwater Locator Beacon (ULB). When immersed in water, the ULB activates and emits an acoustic (ultrasonic) pulse (typically at 37.5 kHz) to guide sonar-equipped searchers. It does not emit light pulses, as light cannot travel effectively through deep ocean water. Statement 2 is Correct: The term "black box" collectively refers to two distinct recording devices (which are sometimes combined into a single unit): the Cockpit Voice Recorder (CVR), which records radio transmissions and sounds in the cockpit, and the Flight Data Recorder (FDR), which records technical flight parameters such as altitude, airspeed, heading, and acceleration. Statement 3 is Correct: The data is stored inside a highly protected component called the Crash-Survivable Memory Unit (CSMU). To survive extreme impact (up to 3,400 Gs), deep-sea pressure, and intense fire (up to 1,100°C), the CSMU's outer armor is manufactured using heavy-duty stainless steel or titanium, layered with thermal insulation. Therefore, option B is the correct answer.

Statement 1 is Correct: The primary goal of stealth technology is to minimize an object's Radar Cross-Section (RCS), making it appear as small as a bird or insect on enemy screens. This is achieved through geometric shaping (to deflect waves away from the source) and by coating the surface with Radar Absorbing Materials (RAM), which absorb electromagnetic radar energy and dissipate it as heat. Statement 2 is Correct: Stealth objects are not completely invisible. Their shapes and RAM coatings are typically optimized to defeat high-frequency radars (like X-band) used for precise weapons targeting. However, they can often be detected by low-frequency radars (such as VHF and UHF bands). The longer wavelengths of these specific frequencies resonate with the aircraft's physical dimensions, allowing detection, though they lack the resolution required for a missile lock. Statement 3 is Incorrect: Metamaterials are artificially engineered structures with unique electromagnetic properties. In advanced stealth applications, they are used to decrease or eliminate radar scattering, not increase it. They achieve this by either perfectly absorbing the electromagnetic radiation or by bending and redirecting the waves smoothly around the object (electromagnetic cloaking) so that no signal scatters back to the radar receiver. Increasing scattering would make the object highly visible, defeating the purpose of stealth. Therefore, the correct option is C.

Statement 1 is Correct: DHRUV64 is the third chip to be fabricated under the Digital India RISC-V (DIR-V) Programme. The first chip was THEJAS32 and the second was THEJAS64. The DIR-V programme aims to create a complete portfolio of future-ready, indigenous RISC-V-based microprocessors to reduce India's dependence on imported chips and foreign intellectual property. Statement 2 is Correct: Developed by the Centre for Development of Advanced Computing (C-DAC) under the Ministry of Electronics and Information Technology (MeitY), DHRUV64 is officially recognized as India's first homegrown 1.0 GHz, 64-bit dual-core microprocessor. It is built on the open-source RISC-V instruction set architecture, which eliminates proprietary licensing fees and ensures technological sovereignty. Therefore, both statements are correct.

Statement 1 is correct: The article states, 'The researchers used a superlattice: atoms of platinum and copper atoms arranged in alternating layers'. Statement 2 is incorrect: The article explicitly states, 'Crucially, the team found that electron pressure, rather than heat, to be the driving force.' Statement 3 is correct: The article mentions, 'The discovery is an advance in the broader field of thermoacoustic metamaterials... The study also demonstrated that these effects can be achieved in materials created by sputtering.'

The article defines strain engineering as: 'it uses mechanical pressure at the atomic level to alter a material’s properties. That is, by physically squeezing or stretching the grid of atoms — called the lattice — scientists can change how a material conducts electricity or stores magnetic information.'

The article states: 'In particular, THz-frequency vibrations are needed for advanced applications like spintronics — a field that uses the magnetic spin of electrons rather than their charge to store and move data.'