Question

Which of the following time measuring devices is most precise ?

• A. A wall clock
• B. An atomic clock
• C. A digital watch
• D. A stop watch

Answer 1

The Correct Option is B

An atomic clock is the most precise time measuring device because atomic oscillations are repeated with a precision of $1 \,s$ in $10^{13}\, s$.

Answer 2

Ans. If a measuring instrument's least count is lower than that of other instruments, it is said to be more accurate. The most accurate method or tool is one that can detect the tiniest change in any unit.

Four types of measurement of time have been mentioned here, and their lowest counts are as follows:

• Wall clock – 1 sec
• Atomic clock – 10⁻¹³ sec
• Digital watch – 0.001 sec
• Stopwatch – 0.1sec

So, the atomic clock is the most precise of all.

A device that uses a hyperfine transition frequency in an electron or microwave transition frequency in the ultraviolet or optical portion of the electromagnetic spectrum of the atoms as a reference frequency to keep the time accurate is referred to as an atomic clock. The clock that is based on working with atoms is known as an atomic clock, sometimes referred to as the main clock. The frequency of the clock is affected by the crossing radiation of electrons.  

• Due to the uniform frequency, atomic clocks provide the most precise time measurement.
• It is sometimes referred to as the system's main standard for distributing time internationally.
• It is used in the global navigation system in satellites and to manage the wave frequency of TV broadcasts.

An atomic clock, like a conventional clock, relies on the oscillation process to maintain a record of time. Oscillation, which is caused by a change in energy, is a periodic and recurrent oscillation about a central value that may even occur between two or more different states.

For instance: Think of a pendulum clock whose timing is determined by the oscillation of the hanging pendulum, which swings back and forth.

• The frequency of the pendulum has a complete bearing on the clock's time.
• Depending on variables such as local gravity, temperature, and pressure, the pendulum's frequency might be off by any amount.
• The frequency of an atomic clock is entirely determined by the oscillation of atoms, which is always thought to be accurate.