Two clocks are being tsted against a standard clock located in the national laboratory. At `10: 00: 00` AM by the standard clock, the readings of the clocks are :

If you are doing an experiment that requires prescision time interval measurements, which of the two clock will you prefer ?
(a) Clock A
(b) Clock B
(c) Either Clock A or B
(d) Neithr A nor B

Explanation

The range of variation over the seven days of observations is 164 s for clock 1 , and 32 s for clock 2. The average reading of clock 1 is much closer to the standard time than the average reading of clock 2. The important point is that a clock is zero error is not as significant for precision work as its variation, because a .zero-error. can always be easily corrected. Hence clock 2 is to preferred to clock 1.