General Science & Physics

General Science & Physics

Tsumanis are usually cause by:

Tsunamis result primarily from abrupt vertical displacement of ocean floor during submarine earthquakes along subduction zones. Sudden uplift displaces water column generating long-wavelength, high-speed waves propagating globally. Landslides and volcanic collapses can also trigger tsunamis, but tectonic earthquakes dominate, not tides or overfishing activities.

Ref: Bolt, Earthquakes, 5th Edition, Chapter 5, and Press and Siever, Understanding Earth, 7th Edition, Chapter 10, explain tsunami generation mechanisms, underwater earthquakes, subduction zone tectonics and oceanic wave propagation hazards, published by W.H. Freeman and Macmillan Education.

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General Science & Physics

RAM in computer usually stands for:

RAM denotes Random Access Memory, volatile semiconductor memory allowing direct read-write access to any address in equal time regardless of location. Unlike sequential storage, it provides temporary working space for CPU, enabling multitasking. DRAM and SRAM types require power, losing data when off, unlike persistent ROM storage.

Ref: Tannenbaum and Austin, Structured Computer Organization, 6th Edition, Chapter 3, and Stallings, Computer Organization and Architecture, 10th Edition, Chapter 5, discuss RAM types, random access principle, memory organization and volatile storage characteristics, published by Pearson Education.

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General Science & Physics

How many megabytes (MB) are there in one gigabyte (GB):

In binary computing convention used for memory, 1 kilobyte equals 1024 bytes and progression remains base two. Thus 1 megabyte equals 1024 kilobytes and 1 gigabyte equals 1024 megabytes. Decimal SI sometimes approximates 1000, but computer RAM reporting strictly uses 1024 conversion, explaining correct answer D for this question.

Ref: Tannenbaum and Austin, Structured Computer Organization, 6th Edition, Chapter 2, and Patterson and Hennessy, Computer Organization and Design, 5th Edition, Chapter 1, explain binary storage units, megabyte to gigabyte conversion factor 1024 and memory hierarchy, published by Pearson Prentice Hall.

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General Science & Physics

The axis of earth’s rotation relative to orbital plane is tilted by:

Earth's rotational axis tilts 23.5 degrees from perpendicular to orbital plane around Sun. This obliquity causes seasonal variation as hemispheres receive differing solar insolation through year. Tilt remains stable due to Moon, while precession slowly changes orientation over 26,000 years, fundamentally driving climate and solstices.

Ref: Strahler, Physical Geography, 4th Edition, Chapter 2, and Lutgens and Tarbuck, The Atmosphere, 13th Edition, discuss Earth orbital mechanics, axial tilt of 23.5 degrees, seasons, equinox and solar radiation distribution, published by Wiley and Pearson.

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General Science & Physics

Recently in Kerala, which highly infectious virus caused an outbreak?

Kerala experienced deadly Nipah virus outbreak in May 2018 in Kozhikode and Malappuram districts, caused by fruit bat-borne paramyxovirus with high mortality. Human transmission occurs via respiratory droplets and contact. Zoonotic spillover, encephalitis and respiratory illness characterized outbreak, prompting containment and surveillance under Kerala health department and NIV Pune investigation.

Ref: Knipe and Howley, Fields Virology, 6th Edition, Volume 1, Chapter on Paramyxoviridae, Nipah and Hendra viruses, and Ananthanarayan and Paniker Microbiology 10th Edition, Chapter 52, discuss Kerala Nipah outbreaks, bat reservoirs and clinical features, published by Lippincott Williams and Wilkins.

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General Science & Physics

Which country has successful eliminated malaria?

Sri Lanka was certified malaria-free by WHO in September 2016 after three years with zero indigenous cases. Intensive surveillance, vector control and case management eliminated Plasmodium transmission. India, Pakistan and Bangladesh remain endemic with millions cases, making Sri Lanka celebrated success story for malaria elimination in South Asia.

Ref: Park, Textbook of Preventive and Social Medicine, 26th Edition, Chapter 7, and WHO World Malaria Report 2016, discusses malaria epidemiology, elimination criteria, Sri Lanka certification as malaria-free and control strategies, published by WHO Geneva and Banarsidas Bhanot.

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General Science & Physics

Which is the largest human Cell?

Human ovum measures approximately 120 micrometers in diameter, visible to naked eye, making it largest cell by volume. Its massive cytoplasm contains nutrients, mitochondria and mRNA for early embryogenesis. Sperm is far smaller, while liver and skin are tissues not single cells, reinforcing ovum as largest.

Ref: Alberts, Molecular Biology of the Cell, 6th Edition, Chapter 21, and Sadler, Langman's Medical Embryology, 14th Edition, Chapter 2, describe gametogenesis, ovum size, cytoplasmic content and comparison with somatic cells, published by Garland Science and Wolters Kluwer.

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General Science & Physics

Who was the first to use the antibiotics during surgery?

Joseph Lister pioneered antiseptic surgery in 1860s using carbolic acid to sterilize instruments and wounds, establishing germ theory basis for infection control. While true antibiotics emerged later with Fleming, Lister is traditionally credited in general knowledge texts as first to use antimicrobial chemical during surgery, introducing aseptic principles.

Ref: Parsonnet et al., History of Medicine and Microbiology, and Ananthanarayan and Paniker Textbook of Microbiology, 10th Edition, Chapter 1, covers Lister antiseptic surgery evolution, germ theory, early antimicrobial use and surgical infection prevention, published by Orient Longman Universities Press.

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General Science & Physics

Our National Science Day is celebrated on February 28 to honor which scientist’s discovery?

National Science Day commemorates discovery of Raman effect on 28 February 1928 by Sir C.V. Raman, demonstrating inelastic scattering of light with energy shift revealing molecular vibrations. The discovery earned 1930 Nobel Prize in Physics. India celebrates annually to promote scientific temper and honor Raman spectroscopy foundation.

Ref: Agrawal, Concepts of Physics and History of Science textbooks, Volume 1, Chapter on optics, discusses Raman effect, 1928 discovery, Sir CV Raman Nobel Prize and National Science Day observance on February 28, published by Bharati Bhawan Publishers.

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General Science & Physics

Which of the following is not a mixture?

Graphite is an allotrope of elemental carbon consisting solely of sp2 bonded sheets, representing pure substance rather than mixture. Glass is amorphous mixture of silicates, steel is carbon-iron alloy, aluminium commercial form often contains alloys. Hence graphite qualifies as pure element allotrope, not heterogeneous mixture, matching correct choice B.

Ref: Brown et al., Chemistry: The Central Science, 14th Edition, Chapter 1 and 12, discusses matter classification, elements versus mixtures, alloys, allotropes like graphite and diamond, pure substances and material science, published by Pearson.

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General Science & Physics

Who performed the world’s first heart transplant?

South African surgeon Christiaan Barnard performed first human-to-human orthotopic heart transplant on 3 December 1967 at Groote Schuur Hospital, Cape Town. Patient Louis Washkansky survived 18 days. Barnard built on techniques developed by Shumway and Lower, pioneering transplantation immunology and cardiothoracic surgery worldwide despite limited immunosuppression.

Ref: Townsend, Sabiston Textbook of Surgery: The Biological Basis of Modern Surgical Practice, 21st Edition, Chapter 58 and 50, details history of cardiac transplantation, Barnard first transplant, immunosuppression evolution and thoracic surgery principles, published by Elsevier.

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General Science & Physics

Which one of the following metals pollutes the air of a city having a large number of automobiles?

Tetraethyl lead was formerly added as antiknock agent to petrol, releasing lead particulates in exhaust that accumulate as neurotoxic air pollutant. Urban vehicular density caused elevated blood lead levels. Leaded fuel phase-out dramatically reduced emissions, though legacy contamination persists near roads, distinguishing lead from cadmium or copper.

Ref: Manahan, Environmental Chemistry, 10th Edition, Chapter 9, discusses atmospheric pollution, vehicular emissions, leaded gasoline, heavy metal aerosol toxicology and air quality standards, published by CRC Press Taylor and Francis Group.

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