Atomic standard time is based on __________.

CONCEPT:

• Time standard: It is a specification for measuring time. It can be classified as the rate at which time passes.
  • At the present time, We use an atomic standard of time.
• The periodic vibrations produced in a cesium atom are the basis for the atomic standard of time.

EXPLANATION:

• At the present time, We use an atomic standard of time.
• The periodic vibrations produced in a cesium atom are the basis for the atomic standard of time.
• Just as the vibrations of a balance wheel regulate an ordinary wristwatch, the vibrations of the cesium atom regulate the rate of this cesium atomic clock.
• In the cesium atomic clock, the time of one second is taken as the time needed for 9,192,631,770 vibrations of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium-133 atom.
• This is called the cesium clock or the atomic clock.
• It is used in the national standards.
• So the correct answer is option 1.