Topic
Puzzles
6 articles
Mathematics
Why do headphones tangle in your pocket?
Nobody ties the knots. The cable goes in loose and comes out with three of them, and it happens to charging cables, skipping ropes and garden hose as well. Two physicists tumbled a string in a box three thousand times to find out why.
Mathematics
Why can’t you comb a hairy ball flat?
Try to brush every hair on a tennis ball flat and you always end up with a crown somewhere. Not usually — always. The same proof says that somewhere on Earth right now, the wind is not blowing at all.
Mathematics
Why are four colors enough for any map?
Draw the most awkward map you can invent and four colors will always be enough to keep every neighbor apart. Everybody guesses the reason immediately, and everybody guesses wrong — including the man whose proof stood unchallenged for eleven years.
Mathematics
Why can’t you fold a piece of paper more than seven times?
Everyone gets stuck at six or seven folds, and fetching a bigger sheet barely helps. The reason has almost nothing to do with how strong your hands are.
Mathematics
Why is every cell in a honeycomb a hexagon?
Bees buy wax with honey, so a comb is really a problem about cost. Thousands of builders working in the dark all reach the same answer, and mathematicians took two thousand years to prove they were right.
Mathematics
Why do two people in your class probably share a birthday?
Thirty children, three hundred and sixty-five days, and no obvious way for two of them to collide. Yet in a class that size a shared birthday turns up about seven times in ten.