MCQ
Which of the following time measuring devices is most precise?
- AA wall clock.
- BA stop watch.
- CA digital watch.
- DAn atomic clock. Give reason for your answer.
✓
Answer
- An atomic clock.
Explanation:
The least count of a wall clock, stop watch, digital watch and atomic clock are 1 sec, $\frac{1}{10}\text{sec},\frac{1}{100}\text{sec and}\ \frac{1}{10^{13}}\text{sec}$ respectively. So atomic clock is most precise.
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