Question

(Q1) what do you mean by least count of an instrument?​

Answer 1

Explanation:

In the science of measurement, the least count of a measuring instrument is the smallest and accurate value in the measured quantity that can be resolved on the instrument's scale. ... For example, a sundial may only have scale marks representing the hours of daylight; it would have a least count of one hour.

Answer 2

ANSWER :-

Least count is the lowest limiting value of the measuring instrument.

Suppose the least count of a screw gauge is given 0.01 cm , so we can measure length up to minimum 0.01 cm, below that we can't measure the length. 

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