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When exposed to certain frequencies of radiation, such as radio waves, the subatomic particles called electrons that orbit an atom’s nucleus will “jump” back and forth between energy states. Clocks based on this jumping within atoms can therefore provide an extremely precise way to count seconds.

## How do atomic clocks measure time?

Atomic clocks measure the actual length of a second, which is the base unit we use to calculate time. According to the International System of Units (SI), the time unit “second” is calculated by the time an atom in a defined state – comprised of the element caesium-133 – takes to oscillate 9,192,631,770 times.

## How does an atomic clock set itself?

Atomic clocks automatically synchronize to a radio signal called WWVB that the National Institute of Standards and Technology (NIST) broadcasts continuously from Fort Collins, Colorado. This signal transmits the official time from the Atomic Clock in Boulder, Colorado.

## How do clocks keep accurate time?

Most clocks and watches today keep time by applying electric energy to a quartz crystal, a system developed in the 1930s. … The lever drives other gears that move the clock hands. Atomic clocks, the world’s most accurate timekeepers, use the natural vibration, or oscillation, of the cesium atom as their resonator.

## What do atomic clocks control timing for?

Atomic clocks are the most accurate time and frequency standards known, and are used as primary standards for international time distribution services, to control the wave frequency of television broadcasts, and in global navigation satellite systems such as GPS.

## How accurate is atomic clock time?

How Does an Atomic Clock Work? With an error of only 1 second in up to 100 million years, atomic clocks are among the most accurate timekeeping devices in history.

## Who keeps the world time?

UTC(NIST) is the coordinated universal time scale maintained at NIST. The UTC(NIST) time scale comprises an ensemble of cesium beam and hydrogen maser atomic clocks, which are regularly calibrated by the NIST primary frequency standard. The number of clocks in the time scale varies, but is typically around ten.

## Will an atomic clock set itself?

Atomic clocks set themselves and automatically adjust for daylight saving time (DST) to provide the most accurate timekeeping standard possible.

## Will my clock change automatically?

With Android, go to Settings > System > Date & Time and toggle on Set Automatically.

## How are atomic clocks synchronized?

Atomic clocks are synchronised with each other by using GPS and sending each other synchronisation signals. In fact, about 200 atomic clocks, all synchronised with each other, are used to define International Atomic Time.

## How do we know the exact time?

When telling the exact time, it helps to look for points around the clock you are familiar with (quarter past, quarter to, half past and the five minute intervals). Then either count on or count back to find the exact time. In other words do a simple addition or subtraction to find the correct time.

## What is the most accurate clock in the world?

Atomic clocks are the most precise timekeepers in the world. These exquisite instruments use lasers to measure the vibrations of atoms, which oscillate at a constant frequency, like many microscopic pendulums swinging in sync.