The second (symbol: s, also abbreviated: sec) is the base unit of time in the International System of Units (SI) (French: Système International d’unités), 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 (24 × 60 × 60 = 86400). Analog clocks and watches often have sixty tick marks on their faces, representing seconds (and minutes), and a "second hand" to mark the passage of time in seconds. Digital clocks and watches often have a two-digit seconds counter. The second is also part of several other units of measurement like meters per second for speed, meters per second per second for acceleration, and cycles per second for frequency.
Although the historical definition of the unit was based on this division of the Earth's rotation cycle, the formal definition in the International System of Units (SI) is a much steadier timekeeper:The second is equal to the duration of 9192631770 periods of the radiation corresponding to the transition between the hyperfine levels of the unperturbed ground state of the 133Cs atom.
Because the Earth's rotation varies and is also slowing very slightly, a leap second is added at irregular intervals to clock time to keep clocks in sync with Earth's rotation.
Multiples of seconds are usually counted in hours and minutes. Fractions of a second are usually counted in tenths or hundredths. In scientific work, small fractions of a second are counted in milliseconds (thousandths), microseconds (millionths), nanoseconds (billionths), and sometimes smaller units of a second. An everyday experience with small fractions of a second is a 1-gigahertz microprocessor which has a cycle time of 1 nanosecond. Camera shutter speeds are often expressed in fractions of a second, such as 1⁄30 second or 1⁄1000 second.
Sexagesimal divisions of the day from a calendar based on astronomical observation have existed since the third millennium BC, though they were not seconds as we know them today. Small divisions of time could not be measured back then, so such divisions were mathematically derived. The first timekeepers that could count seconds accurately were pendulum clocks invented in the 17th century. Starting in the 1950s, atomic clocks became better timekeepers than Earth's rotation, and they continue to set the standard today.
March 25, 2022Play on spotify
February 25, 2022Play on spotify
January 26, 2022Play on spotify
September 30, 2021Play on spotify
March 4, 2021Play on spotify
November 25, 2020Play on spotify
July 7, 2020Play on spotify
November 15, 2019Play on spotify
May 19, 2022
Halifax artist Aquakultre has shared "Lunch," a song he wrote with his partner Joolsannie. The track is from his upcoming record 'Don't Trip,' out July 22.
May 16, 2022
Following up on an initial Zig collaboration that launched in 2019, BBC and Reebok are back together, teaming for a second interpretation of the Zig Kinetica II
May 16, 2022
Diddy opens up 2022 Billboard Music Awards with a performance and stirring monologue.
May 11, 2022
Showcased by the brand’s usual array of suspects, Isaiejah Woldemedin, Timo Moffen,Ilan Kraiem Zeitoun, colour-blocked hoodies and tracksuits take centre stage.
May 8, 2022
CASETiFY and Basquiat’s best-selling collaboration is back, with an all-new range of tech accessories inspired by the iconic artworks of the late artist.
May 4, 2022
Ray J has seemingly confirmed the existence of a second sex tape with Kim Kardashian, but he’s also said he never personally possessed a copy.
May 4, 2022
The star of "The Staircase" also said she was "gunning for Cardi B" to walk her down the aisle at her Vegas wedding.
May 3, 2022
Nearly a decade after the breakout success of "Gangnam Style," the Korean rapper is galloping back with newfound wisdom, humility and artistic inspiration.
April 22, 2022
You can also drop in for sets from Finneas, Billie Eilish, Bishop Briggs, Danny Elfman and more.
April 22, 2022
The national albums chart is dominated by modern classics, as Dua Lipa’s "Future Nostalgia" returns to No. 1 for a third non-consecutive week.
April 20, 2022
Luxury fashion retailer Tessuti has reunited UK rapper Novelist and Billionaire Boys Club for a second high-energy campaign that spotlights new SS22 pieces.
April 11, 2022
Gray is set to release his sophomore LP Superache on June 24. He'll release single "Memories" on Friday
April 5, 2022
'Sellout' becomes one of just a handful of rock LPs to top the Billboard 200 in the 2020s.
April 2, 2022
After rebuilding his old E-Mu SP1200, A-Trak set out to create a new EP, resulting in '10 Second Vol. 1.' The post A-Trak releases EP created from fixed-up vintage sequencer appeared first on Dancing Astronaut.
April 1, 2022
"It was more James than them," the Philadelphia 76ers head coach said in response to a comment about his team losing to the Detroit Pistons on Thursday.
March 30, 2022
The Richmond, Virginia rapper can do a bit of everything. See why his standout "No Dough" is a Song You Need to Know
March 29, 2022
The inaugural drop resulted in a swift sellout. Now, Gap and Dapper Dan are giving consumers a chance to buy the hoodie in a new selection of colorways.
March 29, 2022
Their latest mini-album ‘The Second Step: Chapter One’ has also sold over 800,000 copies The post TREASURE are working on a music video for their viral TikTok hit ‘DARARI’ appeared first on NME.