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15 facts about the time
1. Big Ben - the name is not the tower, and the 13-ton bell that rings inside.
2. At different stages of development of civilization, mankind has used solar, star, water, fire, sand, wheel, mechanical, electrical, electronic and atomic clocks.
3. Atomic clocks have an error of 1 second in the six million years. One second - is 9,192,631,770 oscillations of radiation of cesium-133 atom.
4. The clock is in a clockwise direction - left to right - because in this direction the shadow of a sundial.
5. ancient sundial related to the XV century. BC. e., found in Egypt.
6. There are 24 time zones.
7. number of leap years (with an added day of Feb. 29) must be a multiple of four. There is an exception: years divisible by 100 are not leap years. There is an exception to the exception: years divisible by 400 is a leap. 1900 was not a leap year, but 2000 - it was.
8. There leap seconds.
9. almost all progressive mankind (except the US) does not use the designation AM (ante meridiem - before noon) and PM (post meridiem - afternoon), as there is a lot of confusion (quickly answer the question: what before - 1 AM or 12 AM?).
10. There are: millennium, century, five-year plan, year, quarter, month, ten days, week, day, hour, minute, second, millisecond, microsecond, nanosecond, picosecond, femtosecond, and so on.
11. No one knows exactly why the year is divided into 12 months (this division does not correspond to the lunar or solar calendar). It is believed that the division of hours by 60 minutes due to the Babylonian number system, the basis of which it was not 10 but 60.
12. Although in one minute 60 seconds, in one second 1000 milliseconds.
13. 24 hours sidereal time was 23 hours 56 minutes 4, 091 seconds of mean solar time.
14. on the dial with Roman numerals fourth hour is almost always referred to as IIII, and almost never used IV.
15. «Mistakes of 2000" did not exist. At least, nothing had happened to those who did not spend money for its elimination.
Source: www.artlebedev.ru
via factroom.ru
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