Measurement of Time

 The caesium oscillator the primary standard for time and frequency measurements called the _____.

Write down brief description about caesium clock.

Which of the following is not a unit of time?

$1 \mathrm{m}$ = _____$\times {10}^{-16} \mathrm{ly}$ (Up to correct significant figures.)

Define a second in the context of an atomic clock.

Which of the following is the most accurate device for measuring time?

What is a cesium clock?

In earlier days, movement of the moon was used to calculate the time of the day.

Which of the following is compound?