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104 Inventions and Discoveries Trivia Questions and Answers

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Easy Inventions and Discoveries Trivia Questions

  1. Who pioneered antiseptic surgery by applying germ theory to surgical practice?

    Joseph Lister

    Lister used carbolic acid to reduce microbes in wounds, instruments, and dressings. His methods helped lower infection rates after surgery.

    Easy · Also offered: Ignaz Semmelweis, William Harvey, Rudolf Virchow · Source: Encyclopaedia Britannica

  2. What does a barometer measure?

    Atmospheric pressure

    A barometer measures the pressure exerted by the air above it. Changes in pressure help meteorologists track approaching weather systems.

    Easy · Also offered: Air humidity, Wind speed, Air temperature · Source: Encyclopaedia Britannica

  3. Who was awarded the famous U.S. telephone patent in 1876?

    Alexander Graham Bell

    Bell's patent covered a practical method of transmitting vocal sounds electrically. Other inventors worked on related ideas, making the history of the telephone highly competitive.

    Easy · Also offered: Elisha Gray, Thomas Edison, Antonio Meucci · Source: Encyclopaedia Britannica

  4. Who created the tactile writing system used by blind readers?

    Louis Braille

    Louis Braille was blinded as a small child in his father's leather workshop. As a teenager at a Paris school for blind students in the 1820s he reworked a clumsy military code for reading messages in the dark into a six-dot cell that a fingertip can take in at a single touch.

    Easy · Also offered: Samuel Morse, Alexander Graham Bell, Charles Babbage · Source: Encyclopaedia Britannica

  5. The cosmic microwave background is faint radiation left over from which event?

    The Big Bang

    The cosmic microwave background is the afterglow of the hot, dense early universe, released about 380,000 years after the Big Bang when things had cooled enough for atoms to form and light to travel freely. It was found by accident in 1964 as unexplained hiss in a radio antenna and reaches Earth from every direction at almost exactly the same temperature.

    Easy · Also offered: The formation of the first stars, The collapse of the first black holes, The birth of the Milky Way · Source: Official institutional reference

  6. Who is credited with inventing the cotton gin in 1793?

    Eli Whitney

    Whitney's machine separated cotton fibers from their seeds much faster than hand labor. That efficiency helped make short-staple cotton a major commercial crop in the American South.

    Easy · Also offered: Cyrus McCormick, Elihu Thomson, Samuel Morse · Source: Encyclopaedia Britannica

  7. Who patented dynamite in 1867?

    Alfred Nobel

    Nobel stabilized the highly explosive liquid nitroglycerin by absorbing it into a porous material. The safer-to-handle result was widely used in construction and mining.

    Easy · Also offered: Louis Pasteur, Robert Fulton, Michael Faraday · Source: Official institutional reference

  8. Which British inventor demonstrated a working incandescent lamp around the same time as Edison, then merged his lighting company with Edison's?

    Joseph Swan

    Swan first showed a working lamp in Newcastle in December 1878. His British filament patent turned out to predate Edison's, so in 1883 the rivals merged into the Edison and Swan United Electric Light Company, selling bulbs under the brand Ediswan.

    Easy · Also offered: Humphry Davy, Michael Faraday, William Siemens · Source: Encyclopaedia Britannica

  9. What unit measures electric potential difference?

    Volt

    The volt measures the difference in electric potential between two points, the push that drives current along a wire. It is named for Alessandro Volta, who built the first battery around 1800.

    Easy · Also offered: Watt, Ampere, Ohm · Source: Encyclopaedia Britannica

  10. Which American polymath used a 1752 kite experiment to argue that lightning is electrical?

    Benjamin Franklin

    In June 1752 Franklin flew a kite into a thunderstorm and drew charge down the wet string to a key hanging at the bottom, showing that a storm cloud carries the same electricity as a laboratory spark rather than some separate kind of fire.

    Easy · Also offered: Thomas Edison, Nikola Tesla, Samuel Morse · Source: Encyclopaedia Britannica

  11. Which brothers are associated with the 1783 manned hot-air balloon flight in France?

    The Montgolfier brothers

    Joseph-Michel and Jacques-Etienne Montgolfier built paper-lined balloons that rose when filled with hot air. Their experiments helped launch the era of human flight.

    Easy · Also offered: The Wright brothers, The Lumiere brothers, The Grimm brothers · Source: Encyclopaedia Britannica

  12. Before electric refrigerators, what did most households keep food cold in, restocked by a delivery man every few days?

    Icebox

    An icebox was a wooden cabinet lined with tin or zinc and packed with insulation, holding a block of ice in a compartment at the top with a drip pan beneath. Ice was cut from frozen lakes in winter, stored under sawdust, and brought round by an iceman until electric refrigerators killed the trade in the 1930s.

    Easy · Also offered: Root cellar, Springhouse, Ice house · Source: Encyclopaedia Britannica

  13. What optical component enlarges an object in a simple magnifying glass?

    A convex lens

    A convex lens bends light rays inward as they pass through it, so when the object sits closer than the lens's focal length, the eye sees an enlarged, upright image rather than the object itself.

    Easy · Also offered: A concave lens, A cylindrical lens, A Fresnel lens · Source: Encyclopaedia Britannica, Magnifying glass

  14. Which scientist's pea-plant experiments established the basic laws of inheritance?

    Gregor Mendel

    Mendel found that traits are passed in predictable patterns rather than blending permanently together. His inherited factors were later understood as genes.

    Easy · Also offered: Charles Darwin, Louis Pasteur, Robert Hooke · Source: Official institutional reference

  15. Which chemist organized the periodic table and left gaps for elements not yet discovered?

    Dmitrii Mendeleev

    Mendeleev arranged elements to reveal repeating chemical patterns. His willingness to leave gaps allowed him to predict the properties of unknown elements.

    Easy · Also offered: John Dalton, Antoine Lavoisier, Friedrich Kekulé · Source: Encyclopaedia Britannica

  16. What feature did Mendeleev build into his periodic table?

    gaps for undiscovered elements

    Mendeleev left gaps in the table for elements not yet discovered.

    Easy · Also offered: rows ordered by atomic number, a separate column for the noble gases, a block for the radioactive elements · Source: Encyclopaedia Britannica

  17. What signaling system represents letters with short and long signals?

    Morse code

    Morse code represents letters and numbers through patterns of short and long signals for telegraph communication.

    Easy · Also offered: binary code, Braille code, semaphore code · Source: Encyclopaedia Britannica

  18. Which was the first commercially successful fully synthetic fiber, introduced by DuPont in 1938?

    Nylon

    Nylon was developed at DuPont by a team under Wallace Carothers and reached shops in 1938, first as toothbrush bristles and then as stockings that sold in the millions. Once the United States entered the war, production was redirected to parachutes, ropes and tire cord.

    Easy · Also offered: Rayon, Polyester, Spandex · Source: Science History Institute, Nylon

  19. Which major medical idea did Louis Pasteur help establish?

    germ theory of disease

    Germ theory holds that microorganisms can cause disease. Its acceptance supported sanitation, antiseptic practice, vaccines, and later antibiotics.

    Easy · Also offered: humoral theory, miasma theory, spontaneous generation · Source: Encyclopaedia Britannica

  20. Who discovered penicillin after mold contaminated a bacterial culture in 1928?

    Alexander Fleming

    Fleming noticed that Penicillium mold killed bacteria around it. Later researchers developed methods to purify and mass-produce the antibiotic.

    Easy · Also offered: Louis Pasteur, Paul Ehrlich, Gerhard Domagk · Source: Encyclopaedia Britannica

  21. In what year was Alexander Graham Bell granted his landmark U.S. telephone patent?

    1876

    Bell received the patent as long-distance voice communication was becoming technically feasible. The telephone soon developed into a worldwide network technology.

    Easy · Also offered: 1867, 1883, 1892 · Source: Encyclopaedia Britannica

  22. What did Galileo use for early observations of the heavens?

    A telescope

    Galileo used a telescope for his early observations of the heavens. In 1610, he discovered four moons orbiting Jupiter and observed phases of Venus.

    Easy · Also offered: A quadrant, An astrolabe, A cross-staff · Source: National Air and Space Museum, Galileo's Telescope

  23. The oldest known wheels, from around 3500 BCE, were used for what?

    Shaping pottery

    Turning a lump of clay on a flat spinning disc let a potter's hands shape it into an even, symmetrical pot far faster than building it up by coiling or pinching. Wheels mounted on axles for hauling carts arrived only later, as a separate invention entirely.

    Easy · Also offered: Hauling carts, Grinding grain, Raising water from a well · Source: Encyclopaedia Britannica

  24. In what year did the Wright brothers achieve the first sustained powered airplane flight?

    1903

    The Wright brothers achieved the first sustained, controlled powered airplane flight in 1903. Their first flight at Kitty Hawk, North Carolina, lasted 12 seconds and covered 120 feet.

    Easy · Also offered: 1905, 1908, 1911 · Source: Smithsonian Institution

  25. Who discovered X-rays in 1895?

    Wilhelm Röntgen

    Röntgen discovered that the new rays could pass through soft tissue and expose photographic plates. The discovery quickly transformed medical imaging.

    Easy · Also offered: Marie Curie, Henri Becquerel, Ernest Rutherford · Source: Encyclopaedia Britannica

Medium Inventions and Discoveries Trivia Questions

  1. Who developed the modern ballpoint pen design?

    László Bíró

    Bíró used a small rolling ball to transfer quick-drying ink to paper. The design was less prone to smearing than a traditional fountain pen.

    Medium · Also offered: Lewis Waterman, George Parker, Walter Hunt · Source: Encyclopaedia Britannica

  2. What was the Bessemer process designed to produce efficiently?

    Steel

    The process blasted air through molten pig iron to oxidize excess carbon and other impurities. It greatly reduced the cost and time needed to make steel.

    Medium · Also offered: Glass, Paper, Aluminum · Source: Encyclopaedia Britannica

  3. Who published evidence that blood circulates through the heart and body in 1628?

    William Harvey

    William Harvey published evidence in 1628 demonstrating that blood circulates through the heart and body. His work overturned the long-standing belief that blood was continuously produced and consumed by the body.

    Medium · Also offered: Andreas Vesalius, Edward Jenner, Joseph Lister · Source: Encyclopaedia Britannica

  4. Which scientist proposed continental drift in 1912?

    Alfred Wegener

    Wegener argued that today's continents had once formed a larger landmass, later called Pangaea. He lacked a convincing mechanism, which was supplied decades later by plate tectonics.

    Medium · Also offered: James Hutton, Edwin Hubble, Alfred Nobel · Source: U.S. Geological Survey

  5. Which photographic process, unveiled in Paris in 1839, produced a single image directly on a silvered copper plate?

    daguerreotype

    The daguerreotype fixed a remarkably sharp image on a polished silver-coated copper plate. Each one was unique, because there was no negative from which copies could be made.

    Medium · Also offered: heliograph, calotype, albumen print · Source: Encyclopaedia Britannica

  6. Who proposed the double-helix model of DNA in 1953?

    James Watson and Francis Crick

    James Watson and Francis Crick proposed the double-helix model of DNA in 1953, drawing on crucial X-ray diffraction evidence, including Rosalind Franklin’s famous Photo 51.

    Medium · Also offered: Rosalind Franklin and Maurice Wilkins, Linus Pauling and Robert Corey, Erwin Chargaff and Oswald Avery · Source: Encyclopaedia Britannica

  7. Who is credited with identifying the electron in 1897?

    J. J. Thomson

    Thomson used cathode-ray experiments to show that atoms contained tiny negatively charged particles. The finding overturned the idea that atoms were indivisible.

    Medium · Also offered: James Chadwick, Ernest Rutherford, Robert Millikan · Source: Encyclopaedia Britannica

  8. What phenomenon did Faraday demonstrate by moving a magnet through a coil of wire?

    Electromagnetic induction

    In 1831 Faraday showed that a magnet moving through a coil drives a current around that coil, with no battery anywhere in the circuit. Motion alone makes electricity, and that effect, electromagnetic induction, is how every generator and transformer works.

    Medium · Also offered: Electrostatic induction, Electromagnetic radiation, Electromagnetic resonance · Source: Encyclopaedia Britannica

  9. Which innovation made Gutenberg's printing system practical for many different texts?

    movable metal type

    Individual metal letters could be rearranged and reused, unlike a woodblock carved for just one page. This flexibility helped printing spread rapidly through Europe.

    Medium · Also offered: movable wooden type, carved wooden blocks, engraved copper plates · Source: Encyclopaedia Britannica

  10. What hormone did Banting and Best help isolate?

    Insulin

    Frederick Banting and Charles Best helped isolate insulin, the hormone that regulates blood glucose. Their discovery soon led to insulin being used to treat diabetes.

    Medium · Also offered: Adrenaline, Thyroxine, Cortisol · Source: University of Toronto, The discovery of insulin

  11. Who pioneered smallpox vaccination by using cowpox inoculation in 1796?

    Edward Jenner

    Jenner noticed that milkmaids who had caught cowpox seemed to escape smallpox, and tested the idea by inoculating a gardener's son. The word vaccine comes from vacca, Latin for cow.

    Medium · Also offered: Louis Pasteur, Jonas Salk, Albert Calmette · Source: Encyclopaedia Britannica

  12. Who invented Kevlar while researching strong, lightweight fibers at DuPont?

    Stephanie Kwolek

    Kevlar is an aramid fiber with very high tensile strength for its weight. It is used in protective armor, helmets, cables, and other demanding applications.

    Medium · Also offered: Ruth Handler, Hedy Lamarr, Mary Anderson · Source: Encyclopaedia Britannica

  13. Who revolutionized microscopy by making powerful instruments with a single tiny lens?

    Antonie van Leeuwenhoek

    Leeuwenhoek's carefully made single lenses produced remarkably clear images. He used them to observe microorganisms and other details invisible to the naked eye.

    Medium · Also offered: Robert Hooke, Christiaan Huygens, Giovanni Faber · Source: Encyclopaedia Britannica

  14. Which law let Mendeleev leave gaps in his table and correctly predict the properties of gallium and germanium?

    periodic law

    Mendeleev's periodic law originally related repeating properties to atomic weight. The modern table explains the pattern mainly through atomic number and electron structure.

    Medium · Also offered: law of triads, law of octaves, law of multiple proportions · Source: Encyclopaedia Britannica

  15. Who is credited with developing the first practical microwave oven after noticing radar waves heated food?

    Percy Spencer

    Spencer was working with magnetrons when he noticed that microwave energy melted a candy bar in his pocket. His observation led to a new way of cooking and reheating food.

    Medium · Also offered: Robert Watson-Watt, Hedy Lamarr, Leo Szilard · Source: Encyclopaedia Britannica

  16. In which decade did Samuel Morse develop his electric telegraph system?

    the 1830s

    The telegraph sent coded electrical pulses through wires. It reduced long-distance message delivery from days or weeks to minutes or hours.

    Medium · Also offered: the 1810s, the 1850s, the 1870s · Source: Encyclopaedia Britannica

  17. Who discovered the neutron in 1932?

    James Chadwick

    The neutron is a neutral particle in the atomic nucleus. Its discovery helped explain atomic mass and made later nuclear physics possible.

    Medium · Also offered: J. J. Thomson, Niels Bohr, Enrico Fermi · Source: Encyclopaedia Britannica

  18. In 1885 Louis Pasteur saved a nine-year-old boy, Joseph Meister, with the first successful vaccine against which disease?

    Rabies

    Pasteur had never tried the preparation on a human being. Over ten days he injected Meister with a series of doses made from the dried spinal cords of infected rabbits, starting with cord dried longest and therefore weakest and working up to fresher, more virulent material. Because rabies incubates slowly, the immune response outran the infection. The boy lived, and treatment given after exposure rather than before became a real branch of medicine.

    Medium · Also offered: Anthrax, Cholera, Tuberculosis · Source: Encyclopaedia Britannica

  19. In which decade did penicillin first become available as a mass-produced medicine?

    The 1940s

    Alexander Fleming noticed in 1928 that a stray mould was killing bacteria on one of his plates, but for years nobody could make the drug in useful quantity. It took Howard Florey and Ernst Chain's Oxford team, and then American drug companies switching from surface-grown mould to deep-tank fermentation, to turn it into a manufactured medicine during the Second World War. Output went from barely enough for a handful of patients to enough for the Allied armies in about three years.

    Medium · Also offered: The 1920s, The 1930s, The 1950s · Source: Encyclopaedia Britannica

  20. What sound-recording device did Thomas Edison demonstrate in 1877?

    The phonograph

    Thomas Edison demonstrated the phonograph in 1877, using a tinfoil-covered cylinder to record and play back sound.

    Medium · Also offered: The gramophone, The graphophone, The dictaphone · Source: Smithsonian Institution

  21. Which product did 3M scientist Arthur Fry help create using a removable adhesive?

    Post-it Notes

    Fry's colleague Spencer Silver had made an adhesive that stuck lightly and peeled off cleanly. Fry, tired of bookmarks falling out of his hymn book, turned it into the repositionable note.

    Medium · Also offered: Velcro fasteners, Teflon cookware, Super Glue · Source: National Inventors Hall of Fame, 'Arthur L. Fry'

  22. RADAR began as an acronym. What does it stand for?

    Radio Detection and Ranging

    The US Navy coined the term in 1940. Ranging matters because the system measures distance as well as direction.

    Medium · Also offered: Radio Direction and Reflection, Radio Analysis and Reporting, Rapid Detection and Ranging · Source: US Naval Research Laboratory

  23. Who discovered natural radioactivity in uranium salts in 1896?

    Henri Becquerel

    Becquerel found that uranium emitted penetrating radiation without being exposed to sunlight. Marie and Pierre Curie later investigated radioactivity in other substances.

    Medium · Also offered: Wilhelm Röntgen, Marie Curie, Ernest Rutherford · Source: Encyclopaedia Britannica

  24. What locomotive won the Rainhill Trials in 1829?

    Rocket

    George and Robert Stephenson's Rocket demonstrated an effective combination of boiler, multi-tube design, and exhaust system. The trial helped establish steam locomotion's future.

    Medium · Also offered: Locomotion No. 1, Puffing Billy, Sans Pareil · Source: Encyclopaedia Britannica

  25. A household refrigerator moves heat out of the cabinet using which cycle?

    Compressing and expanding a refrigerant

    Nearly every domestic fridge runs a vapour-compression cycle. The refrigerant is let through a narrow valve into the pipes inside the cabinet, where it expands and boils, taking heat out of the food; the compressor then squeezes that vapour hard enough for it to condense in the coils at the back, dumping the heat into the kitchen.

    Medium · Also offered: Absorbing a refrigerant into a liquid, Passing current through a thermoelectric junction, Evaporating water · Source: Encyclopaedia Britannica

  26. What process strengthens natural rubber by heating it with sulfur?

    Vulcanization

    Sulfur creates cross-links between rubber polymer chains, making the material more durable and less sticky. The process made rubber useful in tires and many industrial products.

    Medium · Also offered: Fermentation, Distillation, Electrolysis · Source: Encyclopaedia Britannica

  27. Who developed the first widely successful inactivated polio vaccine?

    Jonas Salk

    Salk's vaccine used killed poliovirus and was injected. Albert Sabin later developed a different live-attenuated vaccine taken by mouth.

    Medium · Also offered: Albert Sabin, Edward Jenner, Maurice Hilleman · Source: Encyclopaedia Britannica

  28. SCUBA is an acronym. What does it stand for?

    Self-Contained Underwater Breathing Apparatus

    The 'self-contained' part is the whole point: the diver carries their air rather than being fed it from the surface.

    Medium · Also offered: Submersible Compressed Underwater Breathing Apparatus, Sealed Cylinder Underwater Breathing Aid, Surface-Connected Underwater Breathing Apparatus · Source: US Navy Diving Manual

  29. What invention by Elisha Otis made passenger elevators practical?

    The elevator safety brake

    Otis built a catch that grabbed the guide rails if the hoisting rope snapped. He proved it in 1854 by having the rope of his own platform cut in front of a crowd.

    Medium · Also offered: The counterweight, The hydraulic piston, The revolving door · Source: Encyclopaedia Britannica, 'Elisha Otis'

  30. Which farm implement did John Deere redesign in 1837 so that sticky prairie soil slid off it?

    The plow

    Cast-iron plows clogged in the heavy soil of the Midwest. Deere, a blacksmith in Grand Detour, Illinois, shaped a polished steel blade that scoured itself clean as it cut.

    Medium · Also offered: The mechanical reaper, The seed drill, The threshing machine · Source: Encyclopaedia Britannica, 'John Deere'

  31. Which camera did Edwin H. Land put on sale in 1948?

    The Polaroid instant camera

    Land's Model 95 went on sale in Boston in November 1948. It developed a finished print inside the camera in about a minute.

    Medium · Also offered: The Kodak Brownie, The Leica rangefinder, The Rolleiflex twin-lens · Source: Encyclopaedia Britannica, 'Edwin Land'

  32. What textile machine did James Hargreaves invent in the 1760s?

    The spinning jenny

    The spinning jenny let one worker spin several threads at once. The water frame was Arkwright's, the power loom Cartwright's, and the cotton gin Whitney's.

    Medium · Also offered: The water frame, The power loom, The cotton gin · Source: Encyclopaedia Britannica, 'Spinning jenny'

  33. Which device did Mary Anderson patent for use on motor cars?

    The windshield wiper

    Anderson's 1903 patent covered a swinging arm, worked by a lever inside the car, that cleared rain and snow from the windshield.

    Medium · Also offered: The rear-view mirror, The hydraulic brake, The turn signal · Source: US Patent 743,801 (Mary Anderson, 1903)

  34. With its ends left open, what does a thermocouple produce when its two junctions are at different temperatures?

    A voltage

    A thermocouple generates a voltage when its two junctions are at different temperatures, an effect known as the Seebeck effect. The resulting voltage is typically only a few millivolts.

    Medium · Also offered: A current, A resistance, A frequency · Source: National Institute of Standards and Technology, Thermocouples

  35. What cycle moves heat in most modern refrigerators?

    a vapor-compression cycle

    Most modern refrigerators use a vapor-compression cycle, in which a refrigerant repeatedly evaporates and condenses to move heat out of the fridge. The same basic process is also used in air conditioners and heat pumps.

    Medium · Also offered: an absorption cycle, a gas-refrigeration cycle, a Stirling refrigeration cycle · Source: Encyclopaedia Britannica

  36. Who invented Velcro after studying how burrs hooked onto clothing and fur?

    George de Mestral

    De Mestral copied the burr's hook-and-loop structure in a fastener. The name Velcro combines parts of the French words for velvet and hook.

    Medium · Also offered: Elias Howe, Whitcomb Judson, Wallace Hume Carothers · Source: Encyclopaedia Britannica

  37. Who built the first battery to deliver a steady electric current, a stack of zinc and copper discs separated by brine-soaked cloth?

    Alessandro Volta

    Alessandro Volta announced his pile in 1800. Earlier machines could only store a charge and release it in a single spark, so a source of continuous current opened up a whole new field of experiment, and the volt is named after him.

    Medium · Also offered: Michael Faraday, Hans Christian Orsted, Georg Ohm · Source: Encyclopaedia Britannica

  38. Which earlier steam engine did James Watt improve with a separate condenser?

    Newcomen engine

    The Newcomen engine repeatedly heated and cooled its working cylinder, wasting energy. Watt's separate condenser allowed the cylinder to stay hot.

    Medium · Also offered: Savery engine, Stirling engine, Ericsson engine · Source: Encyclopaedia Britannica

  39. In which period did James Watt develop the steam-engine improvements that helped power the Industrial Revolution?

    The 1760s and 1770s

    Watt spotted the waste of heat in a Newcomen engine in 1765 and patented his separate condenser in 1769. He spent the 1770s turning it into a commercial engine in partnership with Matthew Boulton in Birmingham, cutting coal use by around three quarters.

    Medium · Also offered: The 1690s and 1700s, The 1800s and 1810s, The 1850s and 1860s · Source: Encyclopaedia Britannica

Hard Inventions and Discoveries Trivia Questions

  1. Which 3M engineer invented masking tape in the 1920s?

    Richard Drew

    Richard Drew invented masking tape at 3M in 1925 after watching car painters struggle to mask off two-tone paint jobs. He went on to develop cellophane Scotch tape five years later.

    Hard · Also offered: Spencer Silver, Arthur Fry, Patsy Sherman · Source: 3M, Our History

  2. Which ancient masonry binder hardens over years by absorbing carbon dioxide from the air, turning back into the mineral of the stone it was burnt from?

    lime mortar

    Lime mortar is made by burning limestone into quicklime, slaking it with water and mixing it with sand. It sets slowly by reabsorbing carbon dioxide and reverting to calcium carbonate. Roman lime mortar also carries lumps of unmixed lime that dissolve when water reaches a crack and re-deposit as fresh mineral, sealing it.

    Hard · Also offered: clay mortar, gypsum mortar, bitumen mortar · Source: Encyclopaedia Britannica

  3. Which material is generally recognized as the first fully synthetic plastic?

    Bakelite

    Leo Baekeland made Bakelite in 1907 from phenol and formaldehyde, with no natural polymer in it. Celluloid and vulcanized rubber are both treated natural materials.

    Hard · Also offered: Celluloid, Nylon, Vulcanized rubber · Source: Science History Institute, 'Leo Hendrik Baekeland'

  4. Who developed the idea behind the modern barcode?

    Norman Woodland and Bernard Silver

    Norman Woodland and Bernard Silver developed the idea behind the modern barcode and patented it in 1952. Their original design used concentric circles, inspired in part by Morse code.

    Hard · Also offered: Robert Noyce and Jack Kilby, Hedy Lamarr and George Antheil, Ernest Lawrence and Stanley Livingston · Source: Smithsonian National Museum of American History, Barcode

  5. Who discovered the human ABO blood groups?

    Karl Landsteiner

    Landsteiner showed that blood from different people can react differently when mixed. Matching blood groups made transfusions far safer.

    Hard · Also offered: Alexander Fleming, Paul Ehrlich, William Harvey · Source: Encyclopaedia Britannica

  6. How did John Harrison's sea clocks let a navigator work out his longitude?

    By comparing home-port time with local noon

    A clock that kept home time through months at sea let a navigator compare it with local noon. Every hour of difference is 15 degrees of longitude.

    Hard · Also offered: By measuring the ship's speed through the water, By measuring the height of the Pole Star, By timing the swing of a ship's pendulum · Source: Royal Museums Greenwich, 'John Harrison and the Longitude Problem'

  7. What is the angle between magnetic north and true north called?

    Magnetic declination

    A compass needle points at the magnetic pole, not the geographic one, and the gap between the two is called magnetic declination, or variation. It differs from place to place and drifts year by year, which is why walking maps print the local figure along with the date it was measured.

    Hard · Also offered: Magnetic inclination, Azimuth, Bearing · Source: National Oceanic and Atmospheric Administration, Magnetic Compass

  8. Who demonstrated an early computer mouse in 1968?

    Douglas Engelbart

    Douglas Engelbart demonstrated an early computer mouse during his landmark 1968 “Mother of All Demos.” The prototype used knife-edge wheels and had only one button.

    Hard · Also offered: Ken Thompson, Ivan Sutherland, Christopher Strachey · Source: Official institutional reference

  9. Which vehicle, built in 1769, is generally regarded as the first self-propelled road vehicle?

    Cugnot's steam tricycle

    Nicolas-Joseph Cugnot's three-wheeled steam fardier, built in Paris in 1769 to haul artillery, is generally regarded as the first self-propelled road vehicle. It managed walking pace and had to stop every quarter of an hour to raise steam again.

    Hard · Also offered: Trevithick's Puffing Devil, Benz's Patent-Motorwagen, Stephenson's Rocket · Source: Encyclopaedia Britannica

  10. Who partnered with Niépce and continued developing photography after Niépce's death?

    Louis Daguerre

    Daguerre improved photographic exposure and development, eventually creating the daguerreotype. His work helped photography become a public practice.

    Hard · Also offered: William Talbot, Alphonse Giroux, Anselm Feuerbach · Source: Encyclopaedia Britannica

  11. What did Humphry Davy produce in 1802 by passing current between carbon rods?

    an electric arc

    In 1802, Humphry Davy created an electric arc by passing current between two carbon rods. His bright demonstration helped lay the groundwork for later electric arc lamps.

    Hard · Also offered: a spark discharge, a glow discharge, a corona discharge · Source: Encyclopaedia Britannica

  12. Who patented a hand-powered dishwasher with wire racks in 1886?

    Josephine Cochrane

    Cochrane designed racks that held dishes securely while jets of water cleaned them. Her company later became part of the modern KitchenAid dishwasher business.

    Hard · Also offered: Margaret Knight, Stephanie Kwolek, Mary Anderson · Source: Encyclopaedia Britannica

  13. Who developed frequency modulation, the broadcasting method used for FM radio?

    Edwin H. Armstrong

    Armstrong demonstrated wide-band FM in 1935. By varying the frequency rather than the strength of the signal, it shrugged off the static that plagued AM broadcasting.

    Hard · Also offered: Guglielmo Marconi, Lee de Forest, Reginald Fessenden · Source: Encyclopaedia Britannica, 'Edwin H. Armstrong'

  14. What industry first used Carl von Linde's refrigeration system commercially?

    breweries

    Von Linde installed his first commercial machine at Munich's Spaten Brewery in 1873. It let brewers hold lager at cold-fermentation temperatures year-round, instead of relying on ice cut from frozen lakes each winter and stored through summer.

    Hard · Also offered: meatpacking plants, dairy farms, pharmaceutical laboratories · Source: Encyclopaedia Britannica

  15. What was the name of the 1901 car designed by Wilhelm Maybach?

    Mercedes 35 hp

    It was named after Mercedes Jellinek, the daughter of Emil Jellinek, the Austrian businessman who commissioned the car and had raced under the pseudonym Monsieur Mercedes. Its low center of gravity and honeycomb radiator helped it dominate early motor racing.

    Hard · Also offered: Benz Motorwagen, Daimler Phoenix, Panhard et Levassor · Source: Smithsonian Institution

  16. What communication technique did Hedy Lamarr and George Antheil patent in 1942?

    Frequency-hopping spread spectrum

    Their 'Secret Communication System' skipped a radio signal between frequencies so it could not easily be jammed. The idea for keeping both ends in step came from Antheil's work with player-piano rolls.

    Hard · Also offered: Amplitude modulation, Pulse-code modulation, Radar ranging · Source: US Patent 2,292,387 (Hedy Kiesler Markey and George Antheil, 1942)

  17. Whose 1923 patent added a third, all-directions stop position to the traffic signal?

    Garrett Morgan

    Earlier signals flipped straight from stop to go, so cars entering from both directions collided. Morgan's T-shaped signal paused everyone in between, the ancestor of the amber light.

    Hard · Also offered: William Potts, Lester Wire, J. P. Knight · Source: US Patent 1,475,024 (Garrett A. Morgan, 1923)

  18. Who led the team that built the A-0 system, an early compiler that turned symbolic code into machine instructions?

    Grace Hopper

    Hopper's A-0, written for the UNIVAC I around 1952, assembled stored routines into a runnable program. Her later work fed directly into COBOL.

    Hard · Also offered: John Backus, Alan Turing, Konrad Zuse · Source: Encyclopaedia Britannica, 'Grace Hopper'

  19. Who discovered the period-luminosity relation for Cepheid variable stars?

    Henrietta Swan Leavitt

    Leavitt found that the slower a Cepheid pulses, the brighter it truly is. That turned the stars into distance markers, and Hubble used them to show that other galaxies lie far beyond our own.

    Hard · Also offered: Annie Jump Cannon, Cecilia Payne-Gaposchkin, Edwin Hubble · Source: Encyclopaedia Britannica, 'Henrietta Swan Leavitt'

  20. Who showed that Earth has a solid inner core inside its liquid outer core?

    Inge Lehmann

    In 1936 the Danish seismologist explained stray earthquake waves arriving where the liquid core should have blocked them: something solid at the centre was bouncing them back.

    Hard · Also offered: Beno Gutenberg, Andrija Mohorovicic, Charles Richter · Source: Encyclopaedia Britannica, 'Inge Lehmann'

  21. Who demonstrated the first working integrated circuit at Texas Instruments?

    Jack Kilby

    Kilby's germanium chip worked on 12 September 1958. Robert Noyce reached the silicon version independently at Fairchild months later, and the two are usually credited together.

    Hard · Also offered: Robert Noyce, Gordon Moore, Geoffrey Dummer · Source: Nobel Prize, 'Jack S. Kilby - Facts'

  22. Which astronomer, then a graduate student, first recognized the radio pulses that became known as pulsars?

    Jocelyn Bell Burnell

    Bell Burnell spotted a repeating signal in 1967 on the chart paper of a radio telescope she had helped build. The 1974 Nobel for the discovery went to her supervisor and to Martin Ryle, not to her.

    Hard · Also offered: Martin Ryle, Fred Hoyle, Vera Rubin · Source: Encyclopaedia Britannica, 'Jocelyn Bell Burnell'

  23. Who added steam power to a major printing press used by The Times of London in 1814?

    Friedrich Koenig

    Friedrich Koenig introduced steam-powered printing to The Times of London in 1814, greatly increasing the speed of newspaper production. His press could print about 1,100 sheets per hour, far faster than traditional hand-operated presses.

    Hard · Also offered: Richard M. Hoe, William Bullock, James Watt · Source: Encyclopaedia Britannica

  24. LASER is an acronym. What does it stand for?

    Light Amplification by Stimulated Emission of Radiation

    It was named after the earlier MASER, which did the same thing with microwaves rather than light.

    Hard · Also offered: Light Alignment by Sustained Emission of Radiation, Linear Amplification of Stimulated Energy Radiation, Light Absorption by Stimulated Emission of Rays · Source: Gould, 1959

  25. Who patented an important lockstitch sewing machine design in 1846?

    Elias Howe

    Howe's machine used a needle with an eye near its point and a shuttle carrying a second thread. The lockstitch became a foundation of later household and industrial sewing machines.

    Hard · Also offered: Isaac Singer, Walter Hunt, Barthélemy Thimonnier · Source: Encyclopaedia Britannica

  26. William Henry Perkin was trying to synthesize quinine when he accidentally produced which dye?

    Mauveine

    The 18-year-old Perkin was left with a black sludge in 1856 that stained silk a rich purple. Mauveine became the first synthetic dye made on an industrial scale.

    Hard · Also offered: Indigo, Prussian blue, Cochineal · Source: Science History Institute, 'William Henry Perkin'

  27. Who invented a modern air-conditioning system for controlling humidity in a printing plant?

    Willis Carrier

    Carrier's 1902 system controlled humidity so paper would not expand and contract unpredictably. The same technology later became the basis of comfort cooling.

    Hard · Also offered: George Westinghouse, Nikola Tesla, Samuel Morse · Source: Encyclopaedia Britannica

  28. Who made the world’s first surviving photograph in the 1820s?

    Joseph-Nicéphore Niépce

    Niépce used bitumen on a pewter plate in a process called heliography. The surviving image is conventionally known as View from the Window at Le Gras.

    Hard · Also offered: Louis Daguerre, William Henry Fox Talbot, George Eastman · Source: Encyclopaedia Britannica

  29. Who developed the first practical compound steam turbine in 1884?

    Charles Parsons

    Parsons's turbine converted high-pressure steam into rotary motion efficiently. Turbines later became important for electrical generators and fast ships.

    Hard · Also offered: James Watt, Gustaf de Laval, George Stephenson · Source: Encyclopaedia Britannica

  30. Who transmitted the first all-electronic television image in 1927, using a tube he called the image dissector?

    Philo T. Farnsworth

    Farnsworth, then 21, transmitted a single straight line on 7 September 1927. Baird's rival system scanned the picture with a spinning perforated disc rather than electronically.

    Hard · Also offered: John Logie Baird, Vladimir Zworykin, Charles Francis Jenkins · Source: Encyclopaedia Britannica, 'Philo Farnsworth'

  31. Who created Portland cement in 1824?

    Joseph Aspdin

    Aspdin calcined limestone and clay and named the resulting cement for its resemblance to Portland stone. Portland cement became a foundation of modern concrete construction.

    Hard · Also offered: John Smeaton, Louis Vicat, Isambard Kingdom Brunel · Source: Encyclopaedia Britannica

  32. Joseph Marie Jacquard's loom, introduced in the early 1800s, read its weaving patterns from what?

    Punched cards

    The holes in each card decided which warp threads lifted for one pass of the shuttle. Charles Babbage borrowed the idea, and punched cards were still feeding computers 150 years later.

    Hard · Also offered: A chain of wooden pegs, Coloured guide threads, Engraved metal plates · Source: Encyclopaedia Britannica, 'Jacquard loom'

  33. Who launched the world's first liquid-propellant rocket in 1926?

    Robert H. Goddard

    Goddard's gasoline and liquid-oxygen rocket flew from a field in Auburn, Massachusetts on 16 March 1926. It climbed about 41 feet and the flight lasted two and a half seconds.

    Hard · Also offered: Wernher von Braun, Konstantin Tsiolkovsky, Hermann Oberth · Source: Smithsonian National Air and Space Museum, 'Robert Goddard and the First Liquid-Propellant Rocket'

  34. What volcanic material helped ancient Roman harbor concrete remain durable underwater?

    pozzolana

    Pozzolana is volcanic ash that reacts with lime and water to form a durable cement. Roman builders used it in harbor structures that have survived for nearly two millennia.

    Hard · Also offered: fly ash, blast-furnace slag, silica fume · Source: Encyclopaedia Britannica

  35. Who patented the modern safety pin in 1849?

    Walter Hunt

    He reportedly designed it in about three hours while twisting a piece of wire, hoping to pay off a $15 debt. He then sold the entire patent for $400, a fraction of the fortune it went on to earn its buyer.

    Hard · Also offered: Elias Howe, Alfred Nobel, Louis Braille · Source: Smithsonian Libraries, Walter Hunt and the safety pin

  36. SONAR is an acronym. What does it stand for?

    Sound Navigation and Ranging

    Sonar was built for the sea, where sound travels far and light does not, and was named to parallel radar.

    Hard · Also offered: Submarine Object Navigation and Ranging, Sonic Observation and Ranging, Sound Oscillation and Reflection · Source: US Naval History and Heritage Command

  37. Who invented the first practical stethoscope in 1816?

    René Laennec

    Laennec first used a rolled sheet of paper and then developed a wooden tube. The instrument let physicians listen to sounds inside the chest without placing an ear directly on the patient.

    Hard · Also offered: Joseph Lister, William Osler, Edward Jenner · Source: Encyclopaedia Britannica

  38. What calculating machine did Blaise Pascal build in the 1640s?

    The Pascaline

    Pascal began the geared adding machine in 1642 to help his father with tax accounts. Babbage's Difference Engine and Thomas de Colmar's arithmometer came nearly two centuries later.

    Hard · Also offered: The Difference Engine, The arithmometer, The slide rule · Source: Encyclopaedia Britannica, 'Blaise Pascal'

  39. Who isolated artemisinin, a key antimalarial compound, from sweet wormwood?

    Tu Youyou

    Tu combed classical Chinese medical texts for malaria remedies, and a fourth-century line about steeping wormwood in cold water told her that heat was destroying the active compound. She shared the 2015 Nobel Prize.

    Hard · Also offered: Gertrude Elion, Dorothy Hodgkin, Barry Marshall · Source: Nobel Prize, 'Tu Youyou - Facts'

  40. Which inventor is associated with the modern zipper design?

    Gideon Sundback

    Gideon Sundback developed the interlocking-tooth zipper design that became widely practical.

    Hard · Also offered: Eli Whitney, George de Mestral, Josephine Cochrane · Source: Smithsonian National Museum of American History, Zipper

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