Which of the following is the most precise device for measuring length: a vernier callipers with 20 divisions on the sliding scale a screw gauge of pitch 1 mm and 100 divisions on the circular scale an optical instrument that can measure length to within a wavelength of light?

Asked by Abhisek | 1 year ago |  68

##### Solution :-

Least count = $$1- \dfrac{9}{10}= \dfrac{1}{10}$$ = 0.01cm

Least count =$$\dfrac{pitch}{number\; of \;divisions}$$

= $$\dfrac{1}{10000}$$​ = 0.001 cm

least count = wavelength of light = 10-5 cm

= 0.00001 cm

We can come to the conclusion that the optical instrument is

the most precise device used to measure length.

Answered by Pragya Singh | 1 year ago

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