Why hours 24

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Second minute became the second we know and use today. It wasn't until the 16th century that minutes and seconds were widely used, when more accurate mechanical clocks were able to keep up the first-ever clock with a seconds hand dates back to Germany, ca. By the time of the Atomic Age, scientists invented the most-accurate clock ever, the atomic clock, which measures one second by counting off 9,,, energy transitions from the cesium atom. But as accurate as this method of time keeping is purported to be, a few seconds have to be added to to Coordinated Universal Time UTC every decade since Earth's rotation around the sun slows ever so slightly over time.

Scientists have tried to come up with more precise methods of measuring timeMetric time, Decimal time, even a New Earth Time aka "Net Time" but it seems unlikely at this point the current system of time is going anywhere soon. Live Science "How did we come to divide the hour into 60 minutes and the minute into 60 seconds?

Why is a minute divided into 60 seconds, an hour into 60 minutes, yet there are only 24 hours in a day? Scientific American "In today's world, the most widely used numeral system is decimal base 10 , a system that probably originated because it made it easy for humans to count using their fingers.

Their adoption of a base 60 system was probably allowed them to make complex calculations using fractions. The ancient Chinese used a dual time system where they divided the day into 12 so-called, 'double hours', originally with the middle of the first double hour being at midnight.

They also had a separate system in which a day was divided into equal parts called 'ke', that are sometimes translated as 'mark' into English. Because of this inconvenience, much later on, in the year of our era, the number of ke in a day was reduced to 96," says Lomb. While many cultures had their own calendars, there doesn't appear to be evidence for equivalent methods for keeping time.

In , the Swiss watch company Swatch introduced the concept of a decimal Internet Time in which the day is divided into 'beats' so that each beat is equal to 1 minute The beats were denoted by the symbol, so that, for example, denotes a time period equal to six hours. I think that I am safe in stating that there will be no change from the present system of time measurement in the foreseeable future.

Keeping time While our units for measuring time seem to be here to stay, the way we measure time has changed significantly over the centuries. The Ancient Egypitians used sundials and waterclocks, as did several civilisations after them. Hourglasses were also an important time-keeping device before the invention of mechanical and pendulum clocks.

The development of modern quartz watches and atomic clocks has enabled us to measure time with increasing accuracy. Today, the standard definition for time is no longer based on the rotation of the Earth around the Sun, but on atomic time. A second is defined as: "9,,, periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium atom.