Seconds is the basic unit of time in the international system of units, with the symbol S, sometimes marked with English abbreviations as sec.
1 international second is equivalent to: 1/60 minutes; 1/3600 hours; 1/86400 days (time unit of the International Astronomical Union); 1/3 1,557,600? Julian year (time unit of the International Astronomical Union)
Minute, also known as minute, is the unit of measurement of time, and the English word for minute is minute; Hour is an auxiliary unit of time, which is consistent with the basic unit of the international system of units. Except leap second, one hour is generally equal to 3600 seconds, or 60 minutes, or 1/24 days. "H" is often used in English or mathematics.
Extended data
The origin of seconds
Before the Han dynasty, "time" refers to the season, and "time" is equivalent to the current season. There are four seasons in a year, so a year is also called "four seasons".
After the Han dynasty, "time" no longer represents the season, but is used to represent the unit of calculating time. At that time, people divided a day into 12 hours on average, and "one hour" was equal to two hours now. People are used to calling this "hour".
In some classical books, we often see the word "time". Many people mistakenly think that an hour is an hour now, which is actually incorrect. The ancient word "night watch" and "night watch" refers to time, and there are two hours between the first watch and the second watch and the third watch.
Later, people divided the day into 24 parts on average, and each part was still expressed by "time". At this time, "a moment" is an hour now, only half of the past (after the Han Dynasty), and the time referred to is shortened.
Then, people divide an hour into 60 equal parts, each time called 1 minute, and divide 1 minute into 60 equal parts, each time called 1 second. This determines the hours, minutes and seconds.
References:
Baidu Encyclopedia-Second
References:
Baidu Encyclopedia-Time Unit