Precise measurements of physical quantities are a need of science. For example, to ascertain the speed of an aircraft, one must have an accurate method to find its positions at closely separated instants of time. This was the actual motivation behind the discovery of radar in World War II. Think of different examples in modem science where precision measurements of length, time, mass etc. are needed. Also, wherever you can, give a quantitative idea of the precision needed.
(i) Precise measurement of physical quantities time, mass and length, are needed for atomic reactions.
(ii) The vast applications of laser depend on the interval of time and distance second).