Isaac Newton: 4 ideas and puzzles worth knowing

4 ideas and puzzles from Isaac Newton, each explained in a minute and credited to the original work. Free on Savvy.

Newton's two-prism trick proved sunlight hides every color
In 1666 Newton let a sunbeam through a hole in his shutter and a prism, spreading it into a rainbow. Passing a single colored ray through a second prism left it unchanged, while re…
— Isaac Newton, New Theory about Light and Colours
Fire a cannonball fast enough, and it never comes back down
Newton imagined a cannon on an impossibly tall mountain, firing horizontally. A slow ball falls to the ground nearby; a faster one lands farther away; fired fast enough, the ball's…
— Isaac Newton, A Treatise of the System of the World
How many cows does it take to eat a field that keeps growing back?
Isaac Newton posed a puzzle in his algebra textbook: a pasture's grass grows at a constant rate every day, even as cows eat it down. Given how many cows it takes to clear one field…
— Isaac Newton, Arithmetica Universalis
Isaac Newton once settled a dice bet a friend couldn't work out for himself
In 1693, diarist Samuel Pepys wrote to Isaac Newton asking which is more likely: rolling at least one six with 6 dice, at least two sixes with 12 dice, or at least three sixes with…
— Isaac Newton, Samuel Pepys, Newton-Pepys problem

Five ideas worth knowing, every week