Tell me where the minutes and seconds are used in our life.

1. At first, people used the earth's rotation period to determine the "solar day", but the "solar day" will change with the seasons. Later, people observed and calculated the "average solar day", and then divided one "average solar day" into 86,4 copies, one of which was 1s (second).

2. The time taken to run 5m in sports competition is measured in minutes.

3. When a satellite or rocket is launched, the countdown will be prepared before launch, and the time unit will be seconds.

4. Before the end of the basketball game, the countdown will start, and the timing will take seconds.

Extended materials:

Common time units:

century, year, quarter, month, week, day, week, hour, minute and second.

time unit is one of the seven basic units, including length, time, mass, amount of matter, illuminance, current and (thermodynamic) temperature. Time units in this entry are listed in descending order of time.

At present, every day and night is 24 hours, compared with 12 hours in ancient times. When western mechanical clocks and watches were introduced to China, people referred to Chinese and western time points as "big hours" and "hours" respectively. With the popularity of clocks and watches, people forget the "big hour", while the "hour" is still used today.

Generally speaking, the length of a year is taken as the time interval that the sun passes from a certain punctuation mark to the same punctuation mark along the ecliptic on the celestial sphere. Due to the different scale points selected, the definition of year is different, which usually includes:

perihelion year =365.25964 days

sidereal year = 365.25634 solar days (≈ 6: 9: 1 on 365)

tropic year (Bessel year) = 365.389.999999999896