1. Isaac Newton described mathematically which force, explaining why planets orbit the sun and why objects fall to the ground?
Gravity
Newton's law of universal gravitation describes the pulling force between any two masses, from apples to planets.
2. Isaac Newton's three laws of motion describe the relationship between a force and what?
Motion
Newton's laws of motion explain how forces make objects speed up, slow down or change direction.
3. Galileo Galilei built improved versions of which instrument, using it to study the Moon, Jupiter's moons and sunspots?
The telescope
Galileo built more powerful telescopes and used them to make careful observations of the night sky in the early 1600s.
4. Albert Einstein's theory of general relativity describes gravity as what?
A bending of space and time
General relativity describes gravity not as a simple pulling force but as massive objects bending the space and time around them.
5. Einstein's famous equation, showing that mass and energy are related, is usually written as what?
E = mc²
E = mc² shows that a small amount of mass can, in principle, be converted into a huge amount of energy.
6. Marie Curie became famous for studying elements that give off energy, a phenomenon she named what?
Radioactivity
Marie Curie's research on radioactivity led to the discovery of two new elements, polonium and radium.
7. Marie Curie is the only person in history to have won Nobel Prizes in two different what?
Sciences
Marie Curie won the Nobel Prize in Physics in 1903 and the Nobel Prize in Chemistry in 1911, a feat nobody else has matched.
8. In 1956, physicist Chien-Shiung Wu carried out a famous experiment that overturned a long-held assumption in physics called what?
Parity conservation
Wu's experiment showed that parity, the idea that physics should look the same in a mirror, does not always hold. Two theorists who predicted this, Lee and Yang, won the Nobel Prize for it.
9. Mathematician Emmy Noether proved a famous theorem linking symmetry in nature to which other idea in physics?
Conservation laws
Noether's theorem shows that every symmetry in physics, such as time passing the same way everywhere, corresponds to a quantity that is conserved, such as energy.
10. Michael Faraday's work on electricity and magnetism in the 1800s led directly to the invention of what?
The electric motor and generator
Faraday discovered that moving a magnet near a wire could generate electricity, the basic idea behind electric motors and generators.
11. James Clerk Maxwell's equations, published in the 1860s, showed that electricity, magnetism and which other thing were all connected?
Light
Maxwell's equations revealed that light itself is an electromagnetic wave, unifying three things that had seemed separate.
12. Dmitri Mendeleev is best known for organising all the known chemical elements into what?
The periodic table
Mendeleev arranged the elements by their properties in 1869, creating the periodic table still used today.
13. Mendeleev's periodic table was remarkable because he deliberately left gaps in it. Why?
He predicted undiscovered elements would fill them later
Mendeleev left gaps for elements he believed existed but had not yet been found, and later discoveries proved him right.
14. Antoine Lavoisier, who helped identify oxygen and hydrogen as elements, is often called the father of modern what?
Chemistry
Lavoisier's careful experiments in the late 1700s helped turn chemistry into a rigorous, measurement based science.
15. Lavoisier helped establish an important scientific law: that in a chemical reaction, mass is always what?
Conserved, neither created nor destroyed
The law of conservation of mass says the total mass of substances before a reaction equals the total mass afterwards.
16. Marie Curie named one of the two new elements she discovered after her home country. Which country was that?
Poland
Curie named the element polonium after Poland, the country of her birth, even though she carried out her research in France.
17. Rosalind Franklin's X-ray images of DNA, especially one known as Photo 51, were crucial evidence for working out what?
The double helix structure of DNA
Franklin's carefully made X-ray diffraction images showed the helical, twisted shape of the DNA molecule.
18. Rosalind Franklin's DNA data was shown, without her knowledge, to which two scientists who went on to publish the double helix model?
James Watson and Francis Crick
Watson and Crick used Franklin's unpublished X-ray data to help build their model. Franklin died before the Nobel Prize for the discovery was awarded, and Nobel Prizes are not given after death.
19. Charles Darwin proposed that species change over long periods of time through a process he called what?
Natural selection
Natural selection is Darwin's idea that individuals best suited to their environment are more likely to survive and pass on their traits.
20. Charles Darwin's most famous book, published in 1859, laying out his theory of evolution, was called what?
"On the Origin of Species"
"On the Origin of Species" set out Darwin's evidence and reasoning for evolution by natural selection.
21. Gregor Mendel's careful experiments breeding pea plants in a monastery garden laid the foundation for which science?
Genetics
Mendel's pea plant experiments in the 1860s revealed patterns in how traits are passed from parents to offspring, founding the science of genetics.
22. Edward Jenner developed the world's first vaccine in 1796, protecting people against which disease?
Smallpox
Jenner noticed that milkmaids who caught the mild disease cowpox seemed protected from the deadly disease smallpox, and used that observation to create the first vaccine.
23. Alexander Fleming noticed in 1928 that mould had killed off bacteria growing in a laboratory dish, leading to the discovery of what?
Penicillin, the first widely used antibiotic
Fleming's accidental discovery of penicillin gave doctors their first effective antibiotic, able to treat many bacterial infections.
24. Louis Pasteur showed that many diseases were caused by tiny living things, too small to see with the naked eye. What are they usually called?
Germs, or micro-organisms
Pasteur's germ theory of disease showed that micro-organisms, not "bad air" as many believed, caused many illnesses.
25. The heat treatment process named after Louis Pasteur, used to make milk and other foods safer to drink or eat, is called what?
Pasteurisation
Pasteurisation heats food or drink just enough to kill harmful micro-organisms without ruining the taste.
26. Katherine Johnson, an American mathematician working at NASA, hand-calculated the flight path for which 1962 mission?
John Glenn's orbital spaceflight
Katherine Johnson's calculations helped plot the path for John Glenn's orbit of the Earth in 1962, at a time when NASA's early computers were still new and not fully trusted.
27. Katherine Johnson also checked, by hand, the computer's calculations for which 1969 mission?
Apollo 11, the first crewed Moon landing
Before Apollo 11 launched, Katherine Johnson verified the computer generated numbers that would guide the astronauts to the Moon and back.
28. The word "algorithm", meaning a set of step-by-step instructions, comes from the name of which mathematician?
Al-Khwarizmi
Al-Khwarizmi was a mathematician working in Baghdad around 800 AD. His Latinised name, Algoritmi, gave us the word "algorithm".
29. Al-Khwarizmi wrote an influential book that gave its name to which branch of mathematics?
Algebra
The word "algebra" comes from "al-jabr", a term in the title of Al-Khwarizmi's book on solving equations.
30. Which scientist, working around the year 1000, wrote the influential "Book of Optics" explaining how vision works?
Ibn al-Haytham, also called Alhazen
Ibn al-Haytham's Book of Optics carefully explained how light and vision work, and is considered a landmark in the history of science.
31. Ibn al-Haytham's Book of Optics correctly argued that we see objects because of what?
Light travelling from objects into our eyes
Ibn al-Haytham showed that vision works because light travels from objects into the eye, correcting an older Greek idea that the eye sent out rays of its own.
32. Ibn al-Haytham is often credited as an early pioneer of which general approach to studying the world, based on testing ideas with careful experiments?
The scientific method
Ibn al-Haytham insisted on testing ideas through observation and experiment rather than accepting them on authority, an early example of the scientific method.
33. The theorem relating the three sides of a right angled triangle is usually named after which ancient Greek thinker?
Pythagoras
The Pythagorean theorem states that in a right angled triangle, the square of the longest side equals the sum of the squares of the other two.
34. The mathematical relationship behind the Pythagorean theorem was actually known and used long before Pythagoras was born, by which earlier civilisation?
The Babylonians
Clay tablets show that Babylonian mathematicians were using this relationship over a thousand years before Pythagoras, though his name stuck to it.
35. Mathematicians in which country developed the concept of zero as a number in its own right, along with a place value number system?
India
Indian mathematicians, including Brahmagupta, set out rules for using zero as a number, and the place value system they developed spread through the Arab world to Europe.
36. The numerals we use today, 0 to 9, ultimately trace back to which country before they spread through the Arab world to Europe?
India
What are often called "Arabic numerals" in Europe actually originated in India and were carried west by Arab scholars and traders.
37. An ancient Chinese mathematics text called "The Nine Chapters on the Mathematical Art" included early methods for solving what?
Systems of linear equations
"The Nine Chapters", compiled over centuries and finished around 2,000 years ago, included a method for solving systems of equations similar to techniques taught today.
38. Ada Lovelace worked closely with which inventor on his design for an early mechanical computer, the Analytical Engine?
Charles Babbage
Ada Lovelace studied and wrote about Charles Babbage's proposed Analytical Engine, a mechanical computer that was never fully built in his lifetime.
39. Ada Lovelace is often regarded as an early computer programmer because she wrote what?
A detailed set of instructions for the Analytical Engine to follow
Lovelace's notes included a detailed method for the Analytical Engine to calculate a sequence of numbers, one of the first things resembling a computer program.
40. Papermaking, gunpowder, the compass and printing, four of history's most influential inventions, are all credited to which country?
China
These four inventions are often called China's Four Great Inventions, developed over many centuries.
41. Cai Lun, working around 105 AD, is credited with improving the process for making what material?
Paper
Cai Lun refined a method for making paper from plant fibres, cloth and other materials, making it cheaper and easier to produce.
42. China's magnetic compass, which transformed sea navigation, was developed centuries before it became common where?
Europe
The compass was in use in China for navigation well before it became widespread among European sailors.
43. Movable type printing, using individual pieces for each character, was invented in China by Bi Sheng roughly how many centuries before Johannes Gutenberg's printing press appeared in Europe?
About four centuries
Bi Sheng developed movable type printing around 1040, roughly four hundred years before Gutenberg's press became famous in Europe in the mid-1400s.
44. Johannes Gutenberg's mid-1400s invention, which transformed how books were made and shared in Europe, was what?
The movable type printing press
Gutenberg's press let printers set and reuse individual metal letters, making books far quicker and cheaper to produce than copying by hand.
45. Gunpowder, one of China's Four Great Inventions, was first stumbled upon by chemists who were searching for what?
A potion for immortality
Chinese alchemists experimenting with mixtures in search of an elixir of immortality accidentally created an early form of gunpowder.
46. Nikola Tesla is best known for developing which kind of electrical power system, still used to send electricity over long distances today?
Alternating current (AC)
Tesla's work on alternating current helped make it practical to send electricity efficiently over long distances.
47. The Wright brothers achieved the first powered, controlled aeroplane flight in which year?
1903
Orville and Wilbur Wright flew their powered aircraft at Kitty Hawk, North Carolina, in 1903.
48. Wootz steel, an unusually strong and famous early steel later linked to legendary sword blades, was first produced in which country?
India
Wootz steel was produced in southern India from around 2,300 years ago, and was later traded widely and prized for its strength.
49. Alan Turing's codebreaking work during the Second World War focused on decoding messages sent using which German machine?
The Enigma machine
Turing and his colleagues at Bletchley Park built machines that helped crack codes produced by Germany's Enigma machine.
50. Alan Turing's theoretical idea of a simple machine that could, in principle, carry out any calculation is known today as a what?
Turing machine
The Turing machine is a theoretical concept, not a physical device, that became a foundation for the modern science of computing.