Science and Technology
54 solved SSC CGL Science previous year questions on Science and Technology, each with the correct answer and a full explanation.
Q1
Anemometer is an instrument meant for measuring __________ .
✓ Correct answer: c) wind speed
ExplanationAnemometer is a meteorological instrument.It is primarily used to measure wind speed and wind pressure.It plays a crucial role in weather forecasting and environmental monitoring.There are different types, such as cup anemometers and vane anemometers.Hence, the correct answer is "wind speed".
Q2
Which of the following is not an operating system
✓ Correct answer: d) Opera
ExplanationAndroid is an operating system developed by Google, primarily used in mobile devices like smartphones and tablets.Vista refers to Windows Vista, an operating system developed by Microsoft, known for its use in personal computers. iOS is an operating system created by Apple Inc., used in iPhones and iPads.Opera is a web browser, not an operating system.It provides internet browsing services rather than managing hardware and software resources.Hence, the correct answer is "Opera."
Q3
Who was the inventor of frozen foods?
✓ Correct answer: b) Clarence Birdseye
ExplanationClarence Birdseye invented a quick- freezing method in 1924. This method revolutionized the food industry by allowing foods to be frozen quickly, preserving their taste and texture.Birdseye's innovation laid the foundation for the modern frozen food industry.His quick-freezing method is responsible for the variety of frozen foods available today.It enabled consumers to have access to fruits, vegetables, meats, and other perishable items year-round.Hence, the correct answer is "Clarence Birdseye."
Q4
Who invented the electric tram?
✓ Correct answer: c) Fyodor Pirotsky
ExplanationFyodor Pirotsky invented the electric tram.The world’s first electric tram line operated in Sestroretsk near Saint Petersburg in Russia.It was invented in 1881. The main purpose of the electric tram was to collect electricity from overloaded wires.William Harvey was an English physician who made contributions to anatomy and physiology.He describes completely the systemic circulation and properties of blood being pumped to the brain and the rest of the body by the heart.Robert Boyles is best known for Boyle's law.Boyle’s law describes the inversely proportional relationship between the absolute pressure and volume of a gas if the temperature is kept constant within a closed system.James Cook was the navigator who made the detailed map of the Newfoundland region.Hence, the correct answer is “ Fyodor Pirotsky.”
Q5
Who invented the vacuum pump?
✓ Correct answer: a) Otto von Guericke
ExplanationThe first vacuum pump was discovered in 1650 by Otto von Guericke and was headed by the suction pump, which dates to antiquity.A vacuum pump is a device that removes gas molecules from a sealed volume to leave behind a partial vacuum.Cai Lun is traditionally regarded as the inventor of paper and the modern papermaking process.Melitta Bentz is credited with the invention of the coffee filter.William Henry Fox Talbot is best known for his development of the calotype which is an early photographic process.Hence the correct option is “Otto von Guericke”
Q6
Who discovered television?
✓ Correct answer: d) John Baird
ExplanationJohn Baird is known as the Father of Television.He was a Scottish inventor.He is also known for inventing Medical Television.He also got a patent for his experiment.First demonstration of Television by Baird was a 30-line image by reflected light.Michael Faraday invented the electric motor.Joseph Henry is known for constructing strong, practical electromagnets and he built the first electromagnetic motors.Hence, the correct answer is “John Baird”.
Q7
Meter in a vehicle that calculates distance covered by the vehicle is called_________.
✓ Correct answer: b) Odometer
ExplanationOdometer is used for measuring the distance traveled by a vehicle such as a car or a Motorcycle.Speedometer is used to indicate the vehicle speed which is usually combined with a device called an odometer that records the distance traveled.Thermometer is used to measure the temperature of the human body.Kilometer is the unit of measurement of distance.Hence, the correct answer is “Odometer”.
Q8
Who among the following devised the technique IVF (In vitro Fertilization)?
✓ Correct answer: b) Robert Edwards
ExplanationRobert G. Edwards invented the technique of In-vitro Fertilization (IVF).IVF is a process of fertilization where an egg is joined with sperm outside the body, in vitro.He co-developed the treatment together with Patrick Steptoe.In 2010 he was awarded the Nobel Prize in Physiology.Air Commodore Sir Frank Whittle was a Royal Air Force air officer.He is credited with inventing the turbojet engine.Edward Jenner discoverer of vaccination for smallpox.1 is a pioneer in the wireless communications industry, especially in radio spectrum management.Hence, the correct answer is “Robert Edwards”.
Q9
Who discovered colour photography?
✓ Correct answer: d) James Clerk Maxwell
ExplanationJames Clerk Maxwell, a Scottish physicist, is renowned for his formulation of electromagnetic theory.He proposed Maxwell's Equations, which revolutionized the understanding of electromagnetism.Maxwell was the first scientist to successfully unify fundamental forces in nature.He demonstrated that light behaves as an electromagnetic wave, connecting electricity, magnetism, and optics.In 1855, Maxwell suggested the three- colour method, which led to the creation of the first colour photograph.Hence, the correct answer is "James Clerk Maxwell."
Q10
Who invented the waterproof raincoat?
✓ Correct answer: c) Charles Macintosh
ExplanationCharles Macintosh invented waterproof raincoats in 1824. He was a Scottish chemist.Robert Hooke is famous for the discovery of the Living Cell.Cai Lun was a Chinese inventor and is considered as the inventor of paper.William Harvey is famous for correctly describing blood circulation in the body.Hence, the correct answer is "Charles Macintosh".
Q11
Which of the following was invented by Sir Humphry Davy?
✓ Correct answer: c) Safety Lamp
ExplanationSir Humphry Davy invented the Safety Lamp in 1815. The Safety Lamp was designed for use in coal mines.It featured a wick lamp enclosed within a mesh screen to prevent explosions.The lamp provided miners with a safer source of light underground.Davy's invention significantly reduced the risk of explosions in coal mines.This innovation revolutionized safety measures in mining operations.Hence, the correct answer is "Safety Lamp."
Q12
Who invented first working laser?
✓ Correct answer: c) T. H. Maiman
ExplanationThe abbreviation LASER is known for the "Light Amplification by Stimulated emission of Radiation".It was invented by an American physicist Theodore H Maiman in 1960. It is a unidirectional beam of light that is monochromatic in nature.It is also a coherent light beam in which crests and troughs of every wave line up with others.T. H. Maiman wrote the book 'The Laser Odyssey', which elaborates on his experience creating the first LASER.Hence, the correct answer is "T.H. Maiman".
Q13
What was invented by Zacharias Jansen?
✓ Correct answer: c) Microscope
ExplanationA microscope is a device used to view extremely small objects.Zacharias Jansen is credited with inventing the microscope in 1590. This invention revolutionized the study of biology and various other scientific fields.Jansen's microscope consisted of two convex lenses in a tube, allowing for magnification.It enabled scientists to explore the world of cells and microorganisms, leading to groundbreaking discoveries.Hence, the correct answer is "Microscope."
Q14
What was invented by J.B. Dunlop?
✓ Correct answer: c) Rubber Tyre
ExplanationJ.B. Dunlop invented the pneumatic tyre that was first used in bicycles.The patent for it was granted to him on 7th December, 1888. John B. Dunlop was born on February 5th 1840, in North Ayrshire, Scotland.He realized that rubber could withstand the wear and tear of being a tire while retaining its resilience.Pneumatic Tyres came to be known as Dunlop Rubber and Dunlop Tyres.Hence, The correct answer is "Rubber Tyre".
Q15
Who discovered Antarctica?
✓ Correct answer: a) James Cook
ExplanationThe discovery of Antarctica is attributed to Captain James Cook.It was during his second expedition in 1773 that Cook and his crew crossed the Antarctic Circle.Although they didn't set foot on the continent, they encountered icebergs and nearby islands.This expedition marked the first recorded crossing of the Antarctic Circle and contributed significantly to the exploration of the region.James Cook's voyages were pivotal in advancing our understanding of the world's geography.Hence, the correct answer is "James Cook."
Q16
Who invented the electrocardiogram (ECG)?
✓ Correct answer: a) Willem Einthoven
ExplanationWilliam Einthoven invented electrocardiogram.It is a test which is used to measure the electrical activity of the heart.Electrical activity of heat leads to contraction of heart muscles which results in heart pumping.ECG is seen in the form of spikes and sips known as dips.This wave pattern helps in assessment of rhythm and rate of heart.Hence ,the correct answer is "Willem Einthoven".
Q17
Edward Jenner discovered the vaccine for which of the following diseases?
✓ Correct answer: c) Smallpox
ExplanationIn 1796 Edward Jenner discovered the vaccine for smallpox.It is also considered to be the first vaccine ever.BCG stands for 'Bacillus Calmette- Guerin', and is named after the two French scientists who developed the first Tuberculosis vaccine – Albert Calmette and Camille Guerin.The first polio vaccine to be widely used in humans, known as inactivated poliovirus vaccine (IPV) or Salk vaccine.Louis Pasteur developed the earliest effective vaccine against rabies that was first used to treat a human bite victim on 6 July 1885. Hence, the correct answer is “Smallpox”.
Q18
Which one of the following is the brightest star in the Orion Constellation?
✓ Correct answer: c) Rigel
ExplanationRigel is the brightest star in the Orion constellation.It is a blue star of the super giant category.It has a mass of 18 times that of the sun.It si seventh brigtest statr in the sky.Its surface temperature can reach up to 11000K.Multiple stars of the Orion constellation os Eta Orionis. second brightest star of the Orion constellation is Betelgeuse.Alnilam is a large blue supergiant star of the Orion constellation.Hence, the correct answer is "Rigel."
Q19
What is the other name for 'Orion' Constellation?
✓ Correct answer: d) Hunter
ExplanationThe 'Orion' constellation is known by the name 'Hunter.' It is one of the most recognizable constellations in the night sky.Orion is named after a legendary hunter from Greek mythology.The constellation is located on the celestial equator and can be seen from both the Northern and Southern Hemispheres.It is characterized by its distinct pattern of stars, which form the shape of a hunter with a belt and sword.Orion contains several notable stars, including the bright stars Betelgeuse and Rigel.It is also home to the Orion Nebula, a stunning cloud of gas and dust where stars are being born.Hence, the correct answer is "Hunter".
Q20
In March 2019, Superstats, a new metrics to analyse the game of____ was launched by Indian Institute of Technology (IIT) Madras researchers and ESPNcricinfo experts.
✓ Correct answer: a) cricket
ExplanationIn March 2019, the Indian Institute of Technology (IIT) Madras researchers and ESPNcricinfo experts collaborated to launch Superstats, a pioneering metrics system aimed at analyzing the game of cricket.Superstats is designed to provide a more comprehensive and insightful understanding of player and team performances in cricket matches.It incorporates various statistical parameters, including batting, bowling, and fielding data, to generate a holistic assessment of players and teams.This innovative approach aims to go beyond traditional statistics and provide deeper insights into the dynamics of the game.Superstats has been developed as a valuable tool for cricket enthusiasts, analysts, and professionals in the cricketing world.Hence, the correct answer is "Cricket".
Q21
William Crookes was a physical chemist who discovered and named the element _____.
✓ Correct answer: c) thallium
ExplanationWilliam Crookes, a British chemist and physicist, made significant contributions to chemistry and spectroscopy.His notable contributions include the discovery of the element thallium in 1861, which Sir William Crookes himself named.Thallium is a soft, malleable metal with distinct chemical properties.It's worth mentioning that Crookes also conducted pioneering work in the field of vacuum tubes, known as Crookes tubes, which played a crucial role in the development of early electronics and the understanding of cathode rays.He made important contributions to the study of radiation and spectroscopy, but his notable discoveries are primarily related to scientific phenomena and instruments rather than discovering new elements.Hence, the correct answer is "thallium".
Q22
Who invented the atomic battery in
✓ Correct answer: b) Henry Moseley
ExplanationHenry Moseley's work on X-ray spectroscopy and the understanding of atomic structure laid the foundation for the development of atomic batteries.In 1913. Henry Moseley demonstrated the first working prototype of an atomic battery called the "beta cell." The beta cell was a device that used the energy from the decay of a radioactive isotope to generate electricity.Moseley's beta cell utilized beta particles emitted during the radioactive decay process to create an electric current.Moseley's work with the beta cell was an important step in the development of atomic battery technology.Inve ntor Invention/Contribution Ales sand ro Volt a Invented the electric battery (Voltaic Pile) Benj ami n Fran klin Discovered electricity and lightning as electrical phenomena, proposed the concept of positive and negative charges, and conducted the famous kite experiment Loui s Past eur Developed the process of pasteurization to kill harmful bacteria in food and beverages, made significant contributions to the field of microbiology and vaccination | | SSC Hence, the correct answer is “Henry Moseley”.
Q23
Electron was discovered in the year 1897 by
✓ Correct answer: c) J J Thomson
ExplanationThe electron was discovered in the year 1897 by J.J. Thomson.Thomson, a British physicist, conducted a series of experiments using cathode rays in a cathode ray tube.Through his experiments, he observed that cathode rays could be deflected by electric and magnetic fields.He concluded that these rays consisted of negatively charged particles, which he named electrons.Thomson's discovery of the electron laid the foundation for our understanding of atomic structure and the development of modern physics.Scie ntist Discovery Tho mas Ediso n The invention of the practical electric light bulb and phonograph Nikol a Tesla Alternating current (AC) systems and numerous electrical inventions J.J. Tho mso n Discovery of the electron and its properties Isaac Newt on Laws of motion, universal gravitation, and calculus Hence, the correct answer is “J J Thomson”.
Q24
__________was the first person to isolate methane gas. He discovered that methane mixed with air could be exploded using an electric spark.
✓ Correct answer: a) Alessandro Volta
ExplanationAlessandro Volta was the first person to isolate methane gas.He discovered that methane mixed with air could be exploded using an electric spark.An electric spark can ignite a mixture of methane gas and air, causing it to explode.When a sufficient amount of methane gas is present in the air and an electric spark is introduced, it can initiate combustion and lead to an explosive reaction.Scient ist Nati onal ity Inventions/Discover ies Willia m Crook es Briti sh Crookes tube Luis Alvare z Ame rica n Alvarez hypothesis Willia m Thoms on Irish - Scot tish Codified the first two laws of thermodynamics Robert Hooke Lon don Hooke's law Hence, the correct answer is “Alessandro Volta”.
Q25
Which one of the following is the largest recognised constellation?
✓ Correct answer: a) Hydra
ExplanationThe largest recognized constellation among the options listed is Hydra.Hydra is the largest of the 88 modern constellations and is located in the southern celestial hemisphere.It is known for its elongated shape and is commonly depicted as a sea serpent.Hydra stretches across a vast area of the sky, covering a significant portion of the southern hemisphere.With its size and prominence, Hydra holds a prominent place in the night sky and is visible from various parts of the world, particularly from locations closer to the equator.Hence, the correct answer is "Hydra".
Q26
Name the Indian Space Research Organisation (ISRO) chairman and Padma Bhushan awardee who created and unleashed a historical moment when Mars Orbiter became the first Indian spacecraft to enter Martian orbit in a maiden attempt.
✓ Correct answer: b) K Radhakrishnan
ExplanationK Radhakrishnan, the former Chairman of the Indian Space Research Organisation (ISRO) and a Padma Bhushan awardee, spearheaded a historic moment in Indian space exploration.Under his leadership, the Mars Orbiter Mission (MOM) achieved a remarkable feat by becoming the first Indian spacecraft to enter the orbit of Mars in its maiden attempt.This groundbreaking achievement took place in 2014 and garnered international recognition.Radhakrishnan's strategic vision and scientific expertise played a vital role in the success of the mission.His tenure as ISRO chairman witnessed significant advancements, consolidating India's position in the global space arena and inspiring the nation with remarkable feats of space exploration.Hence, the correct answer is "K Radhakrishnan".
Q27
The phrase 'Survival of the fittest' as a way of describing the mechanism of natural selection was coined by______.
✓ Correct answer: c) Herbert Spencer
ExplanationThe phrase 'Survival of the fittest is a way of describing the mechanism of natural selection was coined by Herbert Spencer.He coined the term after reading Darwin’s book ‘On the Origin of Species’. ‘Survival of the fittest’ i.e., the fittest species will survive is a phrase that comes from the principle of natural selection which was given by Charles Darwin.In simple words, it means that the organism that will leave the most copies of itself in the successive generations will survive and the other will be eliminated.Hence, the correct answer is "Herbert Spencer".
Q28
Who founded and named the science of electromagnetism?
✓ Correct answer: d) Andre Marie Ampère
ExplanationAndré-Marie Ampère, a French physicist and mathematician, is credited with founding and naming the science of electromagnetism.In the early 19th century, Ampère conducted extensive experiments and formulated Ampère's law, which quantitatively describes the relationship between electric currents and the resulting magnetic fields.His work established the fundamental connection between electricity and magnetism, laying the groundwork for the development of electromagnetic theory.Ampère's discoveries and mathematical formulations paved the way for subsequent advancements in the field, most notably by James Clerk Maxwell, who further developed Ampère's ideas and formulated Maxwell's equations, providing a comprehensive framework for understanding electromagnetism.Hence, the correct answer is "Andre Marie Ampère".
Q29
Who discovered the first vaccine for smallpox?
✓ Correct answer: b) Edward Jenner
ExplanationSmallpox is an acute contagious disease caused by the variola virus, a member of the orthopoxvirus family.The smallpox vaccine, created by Edward Jenner in 1796, was the first successful vaccine to be developed.He observed that milkmaids who previously had caught cowpox did not catch smallpox and showed that a similar inoculation could be used to prevent smallpox in other people.The World Health Organization launched an intensified plan to eradicate smallpox in 1967. The last known natural case was in Somalia in 1977. In 1980 WHO declared smallpox eradicated.Hence, the correct answer is "Edward Jenner".
Q30
Which scientist discovered the 'Penicillin'?
✓ Correct answer: b) Alexander Fleming
ExplanationAlexander Fleming discovered Penicillin which is an antibiotic.This antibiotic is a broad-spectrum antibiotic and is obtained from the Penicillium notatum.It was discovered in 1928 and can kill a wide range of the bacteria (mostly gram positive) like streptococcus, meningococcus and the diphtheria bacillus and hence prevent us from many diseases like pneumonia, scarlet fever, infections in the mouth, ear, gum, throat, and other respiratory diseases.Antibiotics are substances made from microorganisms like bacteria, fungi, etc., to treat the other microorganisms that cause human disease.Hence, the correct answer is "Alexander Fleming".
Q31
The American scientist Edwin Hubble's name is associated with which of these theories?
✓ Correct answer: d) The Big Bang Theory
ExplanationEdwin Hubble is associated with ‘The Big Bang Theory.’ This theory is an explanation of how our universe was created in the first place.According to the big bang theory, the universe which we know was started with a small singularity and then inflated over 13.8 billion years.The Hubble telescope is named after him.Edwin Hubble's work provided critical evidence supporting the Big Bang Theory Lattice gauge theory is a quantum field theory with gauge symmetries on a space-time lattice.Quantum Chromodynamics theory is about strong interactions between quarks mediated by gluons.Partial coherence theory is about the study of optical effects arising from partially coherent radio and light sources.Hence, the correct answer is "The Big Bang Theory".
Q32
As of January 2020, which of the following countries had NOT independently launched a human into space?
✓ Correct answer: a) India
ExplanationAs of January 2020, only three countries, Russia, the United States of America, and China, have independently launched a human into space.India is preparing to join the exclusive club with its ambitious Gaganyaan mission.Gaganyaan is India's first human space mission, planned for 2022, which aims to send three humans into space.This mission is significant for India as it would make the country the fourth in the world to launch a human into space, putting India on the map as a leading player in the field of space exploration.The mission is a flagship program of the Indian Space Research Organization (ISRO) and it is being undertaken with an aim to boost the country's space technology.Hence, the correct answer is "India".
Q33
What was the theme of the 107 th Indian Science Congress held in Bengaluru?
✓ Correct answer: d) Science and Technology: Rural Development
ExplanationThe theme of the 107th Indian Science Congress held in Bengaluru was Science and Technology:Rural Development.The event was inaugurated by Prime Minister Narendra Modi.To scientists, educators, and researchers engaged in different aspects of scientific developments and technology, Congress is a significant focal point.108th edition of the Indian Science Congress was held at R.T.M. Nagpur University, Nagpur, Maharashtra in Jan 2023.Focal theme: Science and Technology for “Sustainable Development with Women Empowerment”.Hence the correct answer is “Science and Technology: Rural Development”.
Q34
Who among the following scientists invented the Cotton Gin?
✓ Correct answer: c) Eli Whitney
ExplanationCotton Gin, one of the key inventions of the Industrial Revolution that shaped the economy of the Antebellum South, was invented by Eli Whitney.Norman Borlaugh led initiatives worldwide that contributed to the extensive increase in agricultural production termed the Green Revolution and received the Nobel Peace prize.George Washington Carver promoted methods to prevent soil depletion and alternative crops to cotton.Sonny Perdue was a founder and partner in an agricultural trading company in Washington DC.Hence, the correct answer is "Eli Whitney".
Q35
Who among the following scientists invented Kevlar?
✓ Correct answer: c) Stephanie Louise Kwolek
ExplanationStephanie Louise Kwolek invented Kevlar in 1965. Kevlar is a material of exceptional strength and stiffness which is used in protective vests as well as in boats, airplanes, ropes, cables.It has high tensile strength and stability at high temperature.Marry Anderson invented windshield wipers.George Eastman is known for the invention of the Kodak Camera.Steve Wozniak is the co-founder of apple.Hence, the correct answer is "Stephanie Louise Kwolek".
Q36
Name the physicist who is credited with the discovery of the Neutron. This 1932 discovery led to his winning the Nobel Prize.
✓ Correct answer: d) James Chadwick
ExplanationIn 1930, James Chadwick discovered neutral particles emitted by the Beryllium nucleus when bombarded by alpha particles.Further research confirmed the existence of a new neutral particle, which he named the neutron, in 1932. The discovery of the neutron was a groundbreaking contribution to the understanding of atomic structure.James Chadwick was awarded the Nobel Prize in Physics in 1935 for his pivotal discovery of the neutron.The neutron, being electrically neutral, played a crucial role in the development of nuclear physics.Hence, the correct answer is "James Chadwick."
Q37
Who discovered cells in the human body?
✓ Correct answer: b) Robert Hooke
ExplanationCells were first discovered by Robert Hooke, an English scientist, in 1665. He visualized a microorganism through a microscope, confirming cells as fundamental structures in all living organisms.Robert Hooke encountered cells while examining cork, akin to those found in a monastery.Hence, the correct answer is "Robert Hooke."
Q38
Who among the following was the founder of Homeopathy?
✓ Correct answer: a) Samuel Hahnemann
ExplanationHomeopathy, originating in Europe, was founded in 1796 by Samuel Hahnemann.Samuel Hahnemann, a German physician, was born on April 10, 1755, in Meissen, Saxony.Graduating with an MD from the University of Erlangen on August 10, 1779, he contributed significantly to reforming 18th-century medical practices.Hahnemann's fundamental tenet emphasized the individual's unique reaction in health and disease, attributing the cause of illness to the internal environment of the host.Hence, the correct answer is "Samuel Hahnemann."
Q39
Who among the following Indian-American scientists was appointed as the acting chief of staff of the US space agency NASA, in February 2021?
✓ Correct answer: c) Bhavya Lal
ExplanationIndian-American Bhavya Lal assumed the role of acting chief of staff of NASA in February 2021. She played a crucial role as a member of the Biden Presidential Transition Agency Review Team for NASA.Bhavya Lal was entrusted with overseeing the transition of NASA during President Joe Biden's administration.Her appointment signifies the recognition of her expertise and contributions to the space agency.Bhavya Lal's appointment marks a milestone as she takes on a leadership role within NASA, contributing to the agency's mission and objectives.Hence, the correct answer is "Bhavya Lal."
Q40
What was the name of the first artificial satellite Launched by India in 1975?
✓ Correct answer: d) Aryabhatta
ExplanationThe Aryabhata spacecraft, named after the famous Indian astronomer, was India's first satellite.It was completely designed and fabricated in India and launched by a Soviet Kosmos-3M rocket from Kapustin Yar on April 19, 1975. The satellite launch came from an agreement between India and the Soviet Union directed by UR Rao and signed in 1972. Aryabhata was created to experiment with X-ray astronomy, agronomics, and solar physics.The Aryabhata satellite's image appeared on the reverse of the Indian two rupee banknotes between 1976 and 1997. Hence, the correct answer is "Aryabhatta."
Q41
Who among the following developed the Polio vaccine?
✓ Correct answer: a) Jonas Salk
ExplanationThe polio vaccine was developed by Jonas Salk.The World Health Organization has a list of essential medicines that include polio immunisation.Hilary Koprowski made the first effective polio vaccine test in 1950. One of the key figures in the development of contemporary bacteriology is Robert Koch.In 1929, FG Hopkins received the Nobel Prize in Physiology or Medicine.One of the most well-known doctors in London, Edward Jenner is credited with developing the smallpox vaccine.Hence, the correct answer is ‘Jonas Salk.’
Q42
Who among the following is the founder of the field of psychoanalysis?
✓ Correct answer: c) Sigmund Freud
ExplanationSigmund Freud is credited with founding the discipline of psychoanalysis.A collection of ideas and therapy methods known as psychoanalysis partially address the unconscious mind.It is a controversial discipline and its effectiveness as a treatment has been contested.Hence, Sigmund Freud is correct.
Q43
Who among the following was the first to conclude that in a vacuum all objects fall with the same acceleration g and reach the ground at the same time?
✓ Correct answer: b) Galileo Galilei
ExplanationGalileo Galilei was the first person to conclude that in a vacuum all objects fall with the same acceleration g and reach the ground at the same time.Galileo Galilei was the first to realize that all objects descend with the same g-force and touch the earth simultaneously in a vacuum.He has been referred to as the founder of contemporary physics, science, and empirical astronomy.Most people agree that Albert Einstein is among the best scientists of all time.For creating the theory of relativity, he is best known.Hence, “Galileo Galilei” is the correct answer.
Q44
In early 1610, who discovered with his newly invented telescope that Jupiter has four moons?
✓ Correct answer: c) Galileo Galilei
ExplanationGalileo Galilei is credited with discovering Jupiter's four largest moons – Io, Europa, Ganymede, and Callisto – in early 1610 using a telescope he had invented.This discovery provided strong evidence against the geocentric model of the universe and supported the heliocentric model proposed by Nicolaus Copernicus.Hence, the correct answer is 'Galileo Galilei '.
Q45
_______ is reducing the degree or intensity of, or eliminating, pollution.
✓ Correct answer: a) Abatement
ExplanationPollution abatement refers to lowering or completely eliminating its level or intensity.Reclamation, restoration, and resource recovery are a few examples of abatement techniques used to lessen the level or intensity of pollution.Pollution abatement techniques cannot be successfully implemented until the sources of pollution have been fully determined.Urban greenery and its role in pollution abatement is an intriguing and developing topic that requires collaborative work from specialists from other fields because it is closely related to urban planning.Hence, the correct answer is "Abatement".
Q46
Which measuring instrument consists of a metal triangular frame supported on three legs, used to measure the radius of curvature of an object such as lenses and curved mirrors which are spherical in shape?
✓ Correct answer: b) Spherometer
ExplanationA spherometer is a kind of measurement equipment that consists of a triangle frame made of metal that is supported on three legs.The points of the three legs, which lie on the radius, come together to create an equilateral triangle.The accuracy of the measurement of the radius of curvature of a sphere or any curved surface may be achieved with its assistance.Hence, the correct answer is "Spherometer."
Q47
In the early nineteenth century, who demonstrated that there are fourteen space lattices, or regularly repeating arrangements of points in space, that differ in symmetry and geometry?
✓ Correct answer: a) Auguste Bravais
ExplanationFrench physicist Auguste Bravais is renowned for his contributions to crystallography, the development of Bravais lattices, and the articulation of Bravais law.It was established in 1849 by the French crystallographer Auguste Bravais that there are fourteen different kinds of point lattices in three dimensions.He then addressed some basic crystallographic issues, such as the relationship between internal structure and external form, using his lattice theory.Specifically, he demonstrated how we can identify the planes that are most likely to manifest as a crystal's faces based on the lattice structure of the crystal.This theory demonstrates how far we can understand crystal form with a little geometry and a few more presumptions.In addition, Bravais researched hydrography, astronomy, statistics, phyllotaxis, geobotany, magnetism, and the northern lights.Hence, the correct answer is "Auguste Bravais".
Q48
Which scientist suggested that the magnet must also exert an equal and opposite force on the current-carrying conductor?
✓ Correct answer: b) Andre Marie Ampere
ExplanationAn electric current flowing through a conductor produces a magnetic field.The field so produced exerts a force on a magnet placed in the vicinity of the conductor.French scientist André-Marie Ampère (1775–1836) proposed that a magnet must exert an equal and opposite force on a current-carrying conductor.Hence, the correct answer is "Andre Marie Ampere".
Q49
As per physicists and their major contributions/discoveries, Which of the following pair is INCORRECT?
✓ Correct answer: d) Paul Dirac – Liquid helium
ExplanationPaul Dirac – Liquid helium is incorrectly matched as Paul Dirac is known for his contributions to quantum mechanics and quantum field theory, not for research on liquid helium.On July 10, 1908, helium was liquefied for the first time.It was achieved by Dutch physicist Heike Kamerlingh Onnes, who won the Nobel Prize in Physics in 1913 for his low-temperature work that led to the production of liquid helium.Hence the correct answer is "Paul Dirac – Liquid helium".
Q50
In which year was the Doppler effect discovered by Austrian scientist Christian Doppler, that describes the change in frequency of any kind of sound or light wave produced by a moving source with respect to an observer?
✓ Correct answer: c) 1842
ExplanationThe Doppler Effect was first articulated by Austrian physicist Christian Doppler in 1842. It refers to the change in frequency of a wave as perceived by an observer moving relative to the source of the wave.This phenomenon is evident in the changing pitch of a vehicle's horn as it approaches and then moves away from the observer.Hence, the correct answer is "1842".
Q51
In which year did the English scientist Michael Faraday discover benzene in the illuminating gas?
✓ Correct answer: d) 1825
ExplanationThe English scientist Michael Faraday discovered benzene in an illuminating gas in the year 1825. He extracted benzene from cylinders of compressed illuminating gas which had been collected from the pyrolysis of whale oil.Faraday called this newly discovered liquid bicarburet of hydrogen.His discovery of benzene marked an important step in the understanding of hydrocarbons and organic chemistry.Benzene is an important organic chemical compound, and consist of 6 carbon atoms joined in a ring with 1 hydrogen atom attached to each.It is a natural constituent of crude oil and is one of the elementary petrochemicals.Hence, the correct answer is "1825".
Q52
In which year did E Gorter and F Grendel make a breakthrough by examining the surface area of lipids and concluded that the lipid surface surrounding cells must be of two layers?
✓ Correct answer: b) 1925
ExplanationEvert Gorter and François Grendel made their groundbreaking observations regarding the structure of cell membranes in 1925. In 1925, Evert Gorter and François Grendel conducted a pivotal experiment to investigate the structure of cell membranes.They focused on the surface area occupied by lipids, which are a major component of cell membranes.The experiment involved the use of red blood cell membranes, known as erythrocyte membranes.Gorter and Grendel proposed the "lipid bilayer" model based on their observations.Hence the correct answer is "1925".
Q53
In 1845, which German chemist published a method for the synthesis of acetic acid, a natural product containing two carbon atoms?
✓ Correct answer: d) Hermann Kolbe
ExplanationHermann Kolbe was the German chemist who, in 1845, published a method for the synthesis of acetic acid through the reaction of sodium acetate with chloroform.Friedrich Wohler is famous for synthesizing urea in 1828, but not acetic acid.Marcellin Berthelot was a French chemist known for his work on organic chemistry but not for synthesizing acetic acid in 1845. Joseph Gay-Lussac is known for his work on gas laws but did not synthesize acetic acid in 1845. Hence, the correct answer is "Hermann Kolbe".
Q54
Who explained the structure and reproductive system of algae in 1935?
✓ Correct answer: b) F.E. Fritsch
ExplanationF.E. Fritsch was a prominent botanist known for his contributions to the study of algae.In 1935, he published significant work detailing various algal species' structure and reproductive systems.His research provided insights into the classification and biology of algae, helping to establish a clearer understanding of their life cycles and reproductive strategies.Fritsch's work is often referenced in academic studies related to phycology, the study of algae.His contributions laid the groundwork for future research in algal biology and its ecological importance.Hence, the correct answer is "F.E.Fritsch."
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