In chess, what is it called when a king is under attack and cannot escape?
AnswerCheckmate
Checkmate ends the game; stalemate, where a player has no legal move but is not in check, is a draw.
Challenge · Facts & stats
Challenge Based facts & stats
7 fact-checked facts about challenges, competitions and records, each with the reason behind it. 5 more are in today's round and join this page after it closes.
The basics
In a knockout tournament, what happens to the loser of each match?
AnswerThey are eliminated
Single-elimination formats remove each match's loser until one champion remains.
Going deeper
The Elo rating system used to rank chess players is named after whom?
AnswerArpad Elo, a physics professor and chess master
Arpad Elo, a Hungarian-American physics professor, designed the system to estimate players' relative skill.
Who became the first person to swim the English Channel without aids, in 1875?
AnswerMatthew Webb
Captain Matthew Webb swam from Dover to Calais in August 1875 in under 22 hours.
In psychology, what is 'flow'?
AnswerA state of deep, focused absorption in a challenging task
Psychologist Mihaly Csikszentmihalyi found flow tends to happen when a task's difficulty matches a person's skill.
Expert level
The Ansari X Prize, won in 2004, was awarded for what achievement?
AnswerPrivate crewed spaceflight twice within two weeks
SpaceShipOne flew above 100 km twice within two weeks in 2004, showing reusable private spaceflight was possible.
In a round-robin tournament of 8 players where every pair meets once, how many games are played?
Answer28
Each player meets 7 others, and 8 × 7 ÷ 2 removes double counting, giving 28 games.
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