Here are two identical rope ladders with slanting rungs. One falls to the floor, the other onto a table. The ladders are released at the same time and fall freely, but the one on the left falls faster, as if the table is “sucking” it downward. Why does this happen?
Here are five new lateral thinking puzzles to test your wits and stump your friends — play along with us as we try to untangle some perplexing situations using yes-or-no questions.
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Here are the sources for this week’s puzzles. In a couple of places we’ve included links to further information — these contain spoilers, so don’t click until you’ve listened to the episode:
Hotel: Listener Paul Sophocleous
Train: Listener Sean Gilbertson
Safe (more information): Listener David White
Robber (more information): Sharon Ross
Murder: Paul Sloane and Des MacHale, Intriguing Lateral Thinking Puzzles, 1996
If you have any questions or comments you can reach us at email@example.com. Thanks for listening!
AB and CD are consecutive ties across a pair of railroad tracks that appear to meet at O on the horizon, H. If the ties are parallel to the horizon and are equally spaced along the tracks, how can we draw the next tie in this perspective figure?
G.B. Spencer devised this ingenious diagram in 1906: It contains 16 separate chess problems, one on each rank and file. In each case, ignore the pieces not on that rank or file and find a way for White to mate in two moves.
For example, the solution to the problem on the first rank is 1. Bd4 Ke2 2. Ng3#. What are the other 15 solutions?
In 1972, Addison-Wesley published an ad for three textbooks on the back of The American Statistician magazine. The ad began with this line:
Y LUAEB H O DTYO AOOSGL
In Word Ways, David Silverman wrote, “Care to try and figure out the hidden message? Although the slogan doesn’t have the pizzazz of (say) ‘Let Esso put a tiger in your tank’, it does have the advantage of universality; it can equally well be applied to the sale of shoes, ships or sealing wax (or, for that matter, floor wax).”
It’s said that when Frederick the Great hosted Voltaire at Sanssouci Palace, he sent him this puzzling note:
It’s a rebus in French: deux mains sous Pé à cent sous scie? (“two hands under ‘p’ at hundred under saw”) means demain souper à Sanssouci? (“supper tomorrow at Sanssouci?”).
Voltaire replied “Ga!”: Gé grand, A petit! (“big ‘G’, small ‘a’!”) means j’ai grand appétit!, or “I am very hungry!”
More chess masters reside in New York City than in the rest of the United States combined. We’re planning a chess tournament that all American masters are expected to attend, and we want to minimize the total intercity traveling done by the players. The New York players argue that, by this criterion, the tournament should be held in their city. The West Coast players argue that a city should be chosen near the center of the gravity of the players. Where should we hold the tournament?
By Orest Jewetzky. White to mate in two moves.
A city has 10 bus routes. Is it possible to arrange the routes and bus stops so that if one route is closed it’s still possible to get from any one stop to any other (possibly changing buses along the way), but if any two routes are closed, there will be at least two stops that become inaccessible to one another?
A backward chess puzzle by Karl Fabel. What moves must White play to avoid winning?