Question

What is the basis of caesium atomic clock?

Answer 1

Atomic clocks are designed to measure the precise length of a second, the base unit of modern timekeeping. 
The major difference is associated with the element used and the means of detecting when the energy level changes. The first type of atomic clock is the cesium atomic clock. For this type of atomic clock, it employs a beam of cesium atoms. 

Answer 2

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