Question

What is the shape of the wavefront in each of the following case:

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

Answer 1

The correct option is B An atomic clock

Step 1: Find least count of given all clock.

Wall clock: The least count of a wall clock is 1 sec.
Stop watch: The least count of a stop watch is $\frac{1}{10}sec$
Digital clock: The least count of a digital clock is $\frac{1}{100}sec$
An atomic clock: The least count of an atomic clock is $\frac{1}{{10}^{13}}sec$

Step: 2 Compare the least count of given all clock.

As we know that an instrument is considered more precise if its least count is less compared to other measuring device. Atomic clock gives more precise time.

Final Answer: An atomic clock.