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Re: ¡Y para variar..Yucateco!
Me acuerdo perfecto de Cahuich y sé de la fama de los yucas...pero de lo que tú estás hablando es una confusión que hay en todo el mundo...no nada más en Yucatán...te dejo las notas para que lo veas...cualquier reloj digital te marcará las 12 am para la media noche (a menos que tengan la funcionalidad como los de los celulares de cambiarlo a formato de 24 horas).
http://en.wikipedia.org/wiki/12-hour_clock
clock system
12-hour 24-hour
midnight
12:00 a.m.* 00:00
1:00 a.m. 01:00
2:00 a.m. 02:00
3:00 a.m. 03:00
4:00 a.m. 04:00
5:00 a.m. 05:00
6:00 a.m. 06:00
7:00 a.m. 07:00
8:00 a.m. 08:00
9:00 a.m. 09:00
10:00 a.m. 10:00
11:00 a.m. 11:00
noon 12:00 p.m.* 12:00
1:00 p.m. 13:00
2:00 p.m. 14:00
3:00 p.m. 15:00
4:00 p.m. 16:00
5:00 p.m. 17:00
6:00 p.m. 18:00
7:00 p.m. 19:00
8:00 p.m. 20:00
9:00 p.m. 21:00
10:00 p.m. 22:00
11:00 p.m. 23:00
undefined
(midnight)* 24:00
* See section "Confusion
at noon and midnight"
The 12-hour clock is a time conversion convention in which the 24 hours of the day are divided into two periods[1] called ante meridiem (a.m., Latin: "before noon") and post meridiem (p.m., Latin: "after noon").[2] The capitalization and punctuation of a.m. and p.m. may vary (consistently) in different texts. Each period consists of 12 hours numbered 12 (acting as zero),[3] 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11. The indication of noon and midnight in the 12-hour system is disputed.
The 12-hour clock was developed over time from the mid-second millennium B.C. to the 16th century A.D. and was once popular throughout Northern Europe, but is now used as the dominant system in the United Kingdom[citation needed] and some former British colonies, including India and the United States. It is also used informally in most of the world. The notion has received much criticism, yet survives out of tradition.
Contents [hide]
1 History and use
1.1 Use by country
2 Abbreviations
3 Criticism and practical problems
3.1 Confusion at noon and midnight
4 Features of the 12-hour clock
5 Related conventions
5.1 Typography
5.2 Informal speech and rounding off
5.3 Formal speech and times to the minute
5.4 U.S. military speech
6 See also
7 References
8 External links
[edit] History and use
Exeter Cathedral clock, showing the Double-XII numbering scheme.The 12-hour clock can be traced back as far as Mesopotamia and Ancient Egypt,[4] but also has roots in Ancient India.[citation needed] The lengths of the ancient hours varied seasonally, always with 12 hours from sunrise to sunset and 12 hours from sunset to sunrise.[citation needed] In Egypt the hour beginning and ending each half-day (four hours each day) were considered twilight hours.[citation needed] An Egyptian sundial for daylight use[5] and an Egyptian water clock for nighttime use found in the tomb of Pharaoh Amenhotep I,[6] both dating to c. 1500 BC, divided these periods into 12 hours each.
The Romans also used a 12-hour clock: the day was divided into 12 equal hours (of, thus, varying length throughout the year) and the night was divided into four watches. The Romans numbered the morning hours originally in reverse. For example, "3 a.m." or "3 hours ante meridiem" meant "three hours before noon", compared to the modern meaning of "three hours after midnight".[citation needed]
The first mechanical clocks in the 14th century, if they had dials at all, showed all 24 hours, using the 24 hour analog dial, influenced by astronomers' familiarity with the astrolabe and sundial, and their desire to model the apparent
Originalmente publicado por Laurence
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http://en.wikipedia.org/wiki/12-hour_clock
clock system
12-hour 24-hour
midnight
12:00 a.m.* 00:00
1:00 a.m. 01:00
2:00 a.m. 02:00
3:00 a.m. 03:00
4:00 a.m. 04:00
5:00 a.m. 05:00
6:00 a.m. 06:00
7:00 a.m. 07:00
8:00 a.m. 08:00
9:00 a.m. 09:00
10:00 a.m. 10:00
11:00 a.m. 11:00
noon 12:00 p.m.* 12:00
1:00 p.m. 13:00
2:00 p.m. 14:00
3:00 p.m. 15:00
4:00 p.m. 16:00
5:00 p.m. 17:00
6:00 p.m. 18:00
7:00 p.m. 19:00
8:00 p.m. 20:00
9:00 p.m. 21:00
10:00 p.m. 22:00
11:00 p.m. 23:00
undefined
(midnight)* 24:00
* See section "Confusion
at noon and midnight"
The 12-hour clock is a time conversion convention in which the 24 hours of the day are divided into two periods[1] called ante meridiem (a.m., Latin: "before noon") and post meridiem (p.m., Latin: "after noon").[2] The capitalization and punctuation of a.m. and p.m. may vary (consistently) in different texts. Each period consists of 12 hours numbered 12 (acting as zero),[3] 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11. The indication of noon and midnight in the 12-hour system is disputed.
The 12-hour clock was developed over time from the mid-second millennium B.C. to the 16th century A.D. and was once popular throughout Northern Europe, but is now used as the dominant system in the United Kingdom[citation needed] and some former British colonies, including India and the United States. It is also used informally in most of the world. The notion has received much criticism, yet survives out of tradition.
Contents [hide]
1 History and use
1.1 Use by country
2 Abbreviations
3 Criticism and practical problems
3.1 Confusion at noon and midnight
4 Features of the 12-hour clock
5 Related conventions
5.1 Typography
5.2 Informal speech and rounding off
5.3 Formal speech and times to the minute
5.4 U.S. military speech
6 See also
7 References
8 External links
[edit] History and use
Exeter Cathedral clock, showing the Double-XII numbering scheme.The 12-hour clock can be traced back as far as Mesopotamia and Ancient Egypt,[4] but also has roots in Ancient India.[citation needed] The lengths of the ancient hours varied seasonally, always with 12 hours from sunrise to sunset and 12 hours from sunset to sunrise.[citation needed] In Egypt the hour beginning and ending each half-day (four hours each day) were considered twilight hours.[citation needed] An Egyptian sundial for daylight use[5] and an Egyptian water clock for nighttime use found in the tomb of Pharaoh Amenhotep I,[6] both dating to c. 1500 BC, divided these periods into 12 hours each.
The Romans also used a 12-hour clock: the day was divided into 12 equal hours (of, thus, varying length throughout the year) and the night was divided into four watches. The Romans numbered the morning hours originally in reverse. For example, "3 a.m." or "3 hours ante meridiem" meant "three hours before noon", compared to the modern meaning of "three hours after midnight".[citation needed]
The first mechanical clocks in the 14th century, if they had dials at all, showed all 24 hours, using the 24 hour analog dial, influenced by astronomers' familiarity with the astrolabe and sundial, and their desire to model the apparent
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