60 free Isaac Newton trivia questions with answers — science & nature quiz, new questions added Aug 2026.
This Isaac Newton trivia quiz goes well beyond the falling apple. The easy questions cover the landmarks everyone half-remembers: where and when he was born, the Principia, the laws of motion, the prism and the spectrum, and the unit of force that carries his name. From there it moves into the plague years at Woolsthorpe, the priority fight over calculus, the first working reflecting telescope and the odd career turn that made a Cambridge professor the scourge of London's counterfeiters. The hard end is for people who have read a biography or two: the quart-mug baby, the burning mirror brighter than a thousand suns, the dice problem he solved for Samuel Pepys, the South Sea losses, the alchemical papers bought at auction by an economist, the diet rules, the heresy he hid for a lifetime and what a posthumous hair test turned up. Every answer was checked against Newton's encyclopaedia entry before publishing, and the source sentence is stored with each question. If you enjoy this one, our physics and famous physicists quizzes pick up where it leaves off.
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Q 01In which year was Newton's Philosophiae Naturalis Principia Mathematica first published?
1687
The book laid out the laws of motion and universal gravitation and is often called the most important single work in the physical sciences.
Q 02Newton shares credit for inventing calculus with which German mathematician?
Gottfried Wilhelm Leibniz
Both men developed it independently, but it is the German's notation that mathematicians still use, adopted by British mathematicians only after 1820.
Q 03Newton was born at a manor house in which English county?
Lincolnshire
Woolsthorpe Manor, his birthplace, is now a Grade I listed building cared for by the National Trust.
Q 04According to the Julian calendar then used in England, Newton was born on which holiday in 1642?
Christmas Day
By the modern Gregorian calendar the date works out to 4 January 1643, which is why sources disagree about the year.
Q 05Newton was born prematurely. His mother said the newborn could have fit inside what?
A quart mug
His father, also called Isaac, had died three months earlier, so the tiny baby was born into a house already in mourning.
Q 06Newton's widowed mother pulled him out of school at about seventeen to make him take up what?
Farmer
He hated it, and his old headmaster and his uncle talked her into sending him back to school and then on to Cambridge.
Q 07As a schoolboy in Grantham, Newton distinguished himself mainly by building what?
Sundials and model windmills
The turnaround reportedly followed a fight with a schoolyard bully; having beaten him, Newton set out to beat him academically as well.
Q 08Which Cambridge college admitted Newton in June 1661?
Trinity
A descendant of his famous apple tree now grows outside the college's main gate, below the room he lived in as a student.
Q 09Newton entered Cambridge as a 'subsizar', which meant he paid his way by doing what?
Performing valet duties
The arrangement lasted until a scholarship in 1664 covered his costs through to his MA.
Q 10Why did Cambridge University close in 1665, sending Newton home for his 'golden years' of discovery?
The Great Plague
The next two years at Woolsthorpe produced the foundations of calculus, his optics and the law of gravitation.
Q 11How old was Newton when he was appointed Lucasian Professor of Mathematics at Cambridge?
26
He was only the second holder of the chair, and by most accounts a hopeless lecturer whose classes were usually empty.
Q 12Whom did Newton succeed as Lucasian Professor in 1669?
Isaac Barrow
His predecessor had already forwarded Newton's early calculus paper to John Collins as the work of 'an extraordinary genius'.
Q 13According to his assistant Humphrey Newton, what did Newton do when nobody turned up to his lectures?
Gave a shortened lecture to the walls
He would halve the lecture from 30 minutes to 15, fulfil his contract, and go back to his experiments; in his whole career he tutored only three students.
Q 21The burning mirror Newton presented to the Royal Society in 1704 was made up of how many concave mirrors?
Seven
Each was about a foot across; the assembly reportedly boiled gold and may have been the most intense man-made radiation before 1945.
Q 22Newton's early electrostatic generator used a globe of what, rather than the usual sulfur?
Glass
He told the Royal Society that it was a 'good electric' decades before that property was widely known.
Q 23Which astronomer encouraged and paid for the publication of the Principia?
Edmond Halley
The whole project grew out of a nine-sheet tract Newton had sent him in 1684, De motu corporum in gyrum.
Q 14Newton built the first working reflecting telescope to sidestep which flaw of lens telescopes?
Chromatic aberration
His prism experiments convinced him that any lens would split light into colours, so he replaced the objective lens with a mirror.
Q 15Roughly how long was the first reflecting telescope Newton produced in late 1668?
About eight inches
Small as it was, it gave a clearer and larger image than much longer refractors and earned him an invitation to demonstrate it to the Royal Society.
Q 16Newton reported that his new reflecting telescope showed him the crescent phase of which planet?
Venus
He also picked out the four Galilean moons of Jupiter with the same eight-inch instrument.
Q 17Newton ground the mirrors for his telescopes from a custom composition of what?
Speculum metal
He judged the quality of the finished optics using the interference rings that now bear his name.
Q 18What name did Newton give to the multicoloured band of light that emerges from a prism?
Spectrum
He then showed the band could be recombined into white light with a lens and a second prism, proving colour is intrinsic to light.
Q 19In which year did Newton publish Opticks, his book on light and colour?
1704
It ended with a set of 'queries', open questions in which he speculated that light and matter might be convertible into one another.
Q 20In Opticks, Newton argued that light is fundamentally composed of what?
Particles
He still noted wave-like behaviour in thin films, and his mechanical model even anticipated the Goos-Hanchen effect.
Q 24Which term did Newton coin in his 1684 tract De motu corporum in gyrum?
Centripetal force
The tract proved that an inverse-square force toward a centre produces elliptical orbits, the nucleus of the Principia.
Q 25Newton used the Latin word 'gravitas' for the effect we call gravity. What does gravitas literally mean?
Weight
The same root gives English 'gravity' in the sense of seriousness.
Q 26In which edition of the Principia did Newton's line 'hypotheses non fingo' first appear?
The second (1713)
It closes the General Scholium, his answer to critics who called gravity an 'occult' force acting at a distance.
Q 27How long did Newton famously take to solve Johann Bernoulli's 1696 brachistochrone problem?
One night
He submitted the solution anonymously, but Bernoulli reportedly recognised 'the lion by his claw'.
Q 28In 1693 the diarist Samuel Pepys asked Newton for advice on a probability problem involving what?
Throwing dice
Pepys had bet on getting three sixes from eighteen throws; Newton showed the six-throw, one-six bet was the safer wager.
Q 29Newton's first major mathematical discovery, in 1664-65, was a generalisation of which theorem?
Binomial
His version works for any exponent, not just whole numbers, and opened the door to his work with infinite series.
Q 30Newton sorted the cubic plane curves into how many types?
Four
He published 72 of the 78 'species'; a later manuscript shows he had found all 78 but chose not to print the last six.