Search results
Results from the WOW.Com Content Network
There are 60 minutes in an hour, and 24 hours in a day. The hour was initially established in the ancient Near East as a variable measure of 1 ⁄ 12 of the night or daytime. Such seasonal hours, also known as temporal hours or unequal hours, varied by season and latitude.
10 nanoseconds, also a casual term for a short period of time. microsecond: 10 −6 s: One millionth of a second. Symbol is μs millisecond: 10 −3 s: One thousandth of a second. Shortest time unit used on stopwatches. jiffy (electronics) ~ 10 −3 s: Used to measure the time between alternating power cycles. Also a casual term for a short ...
As early as the Bronze-Age Xia dynasty, days were grouped into ten-day weeks known as xún (旬). Months consisted of three xún. The first 10 days were the early xún (上旬), the middle 10 the mid xún (中旬), and the last nine or 10 days were the late xún (下旬). Japan adopted this pattern, with 10-day-weeks known as jun (旬).
Classical antiquity – Broad term for a long period of cultural history centered on the Mediterranean Sea, comprising the interlocking civilizations of ancient Greece and ancient Rome, collectively known as the Greco-Roman world. It is the period in which Greek and Roman society flourished and wielded great influence throughout Europe, North ...
Huygens first used a clock to calculate the equation of time (the difference between the apparent solar time and the time given by a clock), publishing his results in 1665. The relationship enabled astronomers to use the stars to measure sidereal time , which provided an accurate method for setting clocks.
A standard for civil time can specify both time intervals and time-of-day. Standardized time measurements are made using a clock to count periods of some period changes, which may be either the changes of a natural phenomenon or of an artificial machine. Historically, time standards were often based on the Earth's rotational period.
Unequal hours are the division of the daytime and the nighttime into 12 sections each, whatever the season. They are also called temporal hours, seasonal hours, biblical or Jewish hours, as well as ancient or Roman hours (Latin: horae temporales). They are unequal duration periods of time because days are longer and nights shorter in summer ...
The commission rejected the seconds-pendulum definition of the metre the following year because the second of time was an arbitrary period equal to 1/86,400 day, rather than a decimal fraction of a natural unit. Instead, the metre would be defined as a decimal fraction of the length of the Paris Meridian between the equator and the North Pole.