Physics & Materials Science

The description mentions three spacecraft in an equilateral triangle formation with million-kilometre sides using lasers for measurement.
This matches the design of the Evolved Laser Interferometer Space Antenna (eLISA) mission.
eLISA is a proposed space observatory aiming to detect gravitational waves using precisely positioned spacecraft. Voyager-2 and New Horizons are single spacecraft on exploration missions, not designed for gravitational wave detection. LISA Pathfinder was a precursor mission to test technologies for eLISA, not the full mission itself. Therefore, based on the details provided, the experiment refers to the Evolved LISA mission.

Steel slag can be used for several purposes, and all of the options listed are valid applications. Statement 1 is correct. Steel slag is a common and cost-effective material for use in road base construction due to its high durability, strength, and drainage properties. Statement 2 is correct. Crushed steel slag can be used as an amendment for agricultural soil. It can improve drainage, provide some essential nutrients, and even help suppress weeds. Statement 3 is correct. Steel slag can be partially substituted for some raw materials in cement production, reducing the need for quarrying and lowering the environmental impact of cement manufacturing. Therefore, the correct answer is 1, 2, and 3.

Pair 1 is incorrect: The Belle II experiment is a particle physics experiment designed to study the properties of B mesons. It is not related to artificial intelligence. Pair 2 s correct: Blockchain technology is the underlying technology behind cryptocurrencies like Bitcoin. It is a distributed ledger technology that ensures secure and transparent transactions. Pair 3 is incorrect: CRISPR-Cas9 is a gene-editing technology used in the field of molecular biology to edit genes. It is not related to particle physics. Therefore, only pair 2 is correctly matched.

Statement 1 is correct: According to Einstein's General Theory of Relativity, gravity can bend light. This phenomenon is known as gravitational lensing. Statement 2 is correct: The General Theory of Relativity led to the prediction of an expanding universe, which has been confirmed by observational evidence. Statement 3 is correct: According to the General Theory of Relativity, the presence of matter and energy warps the fabric of space and time around it, which is the underlying cause of the gravitational force. So, all three statements are correct.

* The terms 'Event Horizon', 'Singularity', 'String Theory' and 'Standard Model' are associated with the observation and understanding of the Universe, particularly in the field of cosmology and astrophysics. * Event Horizon refers to the boundary around a black hole, beyond which nothing, not even light, can escape the black hole's gravitational pull. * Singularity refers to a point in spacetime where the gravitational field becomes infinite, such as at the center of a black hole, where the laws of physics as we know them break down. * String Theory is a theoretical framework in particle physics that attempts to unify all the fundamental forces of nature, including gravity, into a single coherent model. * Standard Model is the most comprehensive and well-tested theory in particle physics, which describes the fundamental particles and their interactions, except for gravity.

The movie The Man Who Knew Infinity is based on the life of the famous Indian mathematician Srinivasa Ramanujan. It portrays his journey from India to England and his collaboration with the British mathematician G.H. Hardy.

IceCube is a particle detector at the South Pole that records the interactions of a nearly massless subatomic particle called the neutrino. IceCube searches for neutrinos from the most violent astrophysical sources, events like exploding stars, gamma-ray bursts, and cataclysmic phenomena involving black holes and neutron stars. Statement 1 is correct: IceCube is the world's largest neutrino detector, encompassing a cubic kilometre of ice. Statement 2 is correct: The IceCube telescope is a powerful tool to search for dark matter and could reveal the physical processes associated with the enigmatic origin of the highest energy particles in nature. Statement 3 is correct: It is buried beneath the surface, extending to about 2,500 meters. Burying it deep in ice is important to enhance the precision of the detector. In addition to exploring the background of neutrinos produced in the atmosphere, IceCube studies the neutrinos themselves; their energies far exceed those produced by accelerator beams. Thus, all three statements are correct.

Statement 1 is correct: Agni-IV is indeed a surface-to-surface missile. It is designed to launch from land-based mobile platforms and strike targets on the ground. Statement 2 is incorrect: Agni-IV is a two-stage, solid-fueled missile. It does not rely on liquid propellants. Statement 3 is also incorrect: The reported range of Agni-IV is around 4,000 km, not 7,500 km. Additionally, its payload capacity is estimated to be around 1,000 kg (one tonne), but its specific warhead capabilities are not publicly disclosed.

Crystallization of sodium chloride: This is a physical change. The sodium chloride (table salt) is changing its form from a dissolved state in water to a solid crystal structure, but the chemical composition remains NaCl. Melting of ice: Similar to crystallization, melting of ice is a physical change. Water (H2O) molecules are rearranging from a rigid solid structure to a more fluid liquid state, but the chemical makeup stays the same. Souring of milk: This is a chemical change. Milk sugar (lactose) is broken down by bacteria into lactic acid. This process involves the formation of new substances and alters the chemical composition of the milk. Therefore, only statement 3 is an example of a chemical change.

An optical illusion is a perception that differs from physical reality, often caused by atmospheric effects or the brain's processing of visual information. Size of the sun at dusk is an optical illusion: The sun appears larger near the horizon than when it's high in the sky, even though its actual angular size is unchanged. This is a psychological illusion caused by our brain misinterpreting distance cues. Colour of the sun at dawn is an optical illusion: The sun appears red because its light travels through more of the atmosphere, which scatters away blue light. This phenomenon, known as Rayleigh scattering, creates a perception of color that differs from the sun's actual light. Moon being visible at dawn is not an optical illusion: This is a real astronomical event. The moon is often in a position in its orbit where it is bright enough to be seen during daylight hours. The twinkle of stars in the sky is an optical illusion: Stars don't actually blink. Their light is refracted by turbulent layers in Earth's atmosphere, causing their apparent brightness to change rapidly, which we perceive as twinkling. Polestar being visible in the sky is not an optical illusion: This is a real phenomenon based on celestial mechanics. The Polestar's apparent fixed position is due to its close alignment with the Earth's axis of rotation