Chinese reign era names were reused by rival courts, and most Ming and Qing emperors began theirs at New Year
Chinese emperors named their years by era names, and a date was written as the era plus a year count. Catalogues disagre...
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Field-test formulas for VO2 max put the same run at very different values
Field tests estimate VO2 max, the most oxygen the body can use per minute for each kilogram of body weight, from a timed...
The clock rule taught for crosswind reads high, most of all at sixty degrees
The crosswind on a runway is the wind speed times the sine of the angle between wind and runway, and flight training tea...
Most Chinese characters share their four-corner code with other characters
The four-corner code turns the stroke shapes at a Chinese character's corners into digits, a lookup method Wang Yunwu ma...
Naegele's rule and the 280-day count give different pregnancy due dates more often than not
A due date is counted from the first day of the last period, either by adding 280 days or by adding nine months and seve...
Riegel's race-time formula comes within about 2% of world records and predicts recreational marathons too fast
Riegel's formula scales a known race time to another distance using an exponent, usually 1.06. Tested against world reco...
Tempo charts disagree on how many beats a minute Andante means
Six published sources give Andante anywhere from 56 to 108 beats a minute, and by our count only 76 and 77 fall inside a...
Glasgow Coma Scale totals hide the eye, verbal and motor scores behind them
A Glasgow Coma Scale total adds three separate observations of the eyes, speech and movement, and the same total can be...
Cake tin size charts hold up on area swaps and vary on cups
Scaling a recipe to another cake tin by base area keeps the batter as deep as the recipe intended, while the tin's capac...
Warm water shifts a pipe's Reynolds number more than the laminar limits differ
Physics texts put the end of laminar pipe flow at a Reynolds number of 2,000 or 2,300, depending on the source, and Reyn...
Equations estimating a one-repetition maximum match on heavy sets and diverge as reps climb
A one-rep max is the heaviest weight a person can lift once, and published equations estimate it from a lighter set take...
Jet lag by direction, worked through on routes out of Singapore and Hong Kong
Flying east asks the body clock to run earlier and flying west asks it to run later, and early estimates from real fligh...
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