Q 11-01-207JEE MainJEE Main 2020 (3 Sep, Shift 1)Medium
Using screw gauge of pitch $0.1\ \text{cm}$ and $50$ divisions on its circular scale, the thickness of an object is measured. It should correctly be recorded as,
Answer: (B) $2.124\ \text{cm}$
Least count $= \dfrac{0.1}{50} = 0.002$ cm. Every reading must be a multiple of $0.002$ cm; among the options only $2.124$ cm is.
Solution by Sreeraj P, M.Sc Physics