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Second

3:48

HYO 효연 'Second (Feat. 비비 (BIBI))' MV

0:46

30 Second Timer

3:51

Sleaford Mods - Second

3:43

HYO(효연) - Second (Feat.BIBI (비비)) (Music Bank) | KBS WORLD TV 210813

3:51

[HYO - Second (Feat. BIBI)] Comeback Stage | #엠카운트다운 EP.720 | Mnet 210812 방송

The second is the SI base unit of time, commonly understood and historically defined as ​1⁄86400 of a day – this factor derived from the division of the day first into 24 hours, then to 60 minutes and finally to 60 seconds each. Another intuitive understanding is that it is about the time between beats of a human heart. Mechanical and electric clocks and watches usually have a face with 60 tickmarks representing seconds and minutes, traversed by a second hand and minute hand. Digital clocks and watches often have a two-digit counter that cycles through seconds. In common parlance, a "clock tick" is a second, though most modern clocks are digital electronic, and do not actually tick. The second is also part of several other units of measurement like velocity, acceleration, and frequency.
    • Clocks and solar time 

    • Events and units of time in seconds 

    • Timekeeping standards 

    • Optical lattice clock 

    • History of definition 

    • SI multiples