Using screw gauge of pitch 0.1cm and 50 divisions on its circular scale,
Question:

Using screw gauge of pitch $0.1 \mathrm{~cm}$ and 50 divisions on its circular scale, the thickness of an object is measured. It should correctly be recorded as:

1. $2.123 \mathrm{~cm}$

2. $2.125 \mathrm{~cm}$

3. $2.121 \mathrm{~cm}$

4. $2.124 \mathrm{~cm}$

Correct Option: , 4

Solution:

$\mathrm{LC}=\frac{\text { pitch }}{\text { CSD }}=\frac{0.1 \mathrm{~cm}}{50}=0.002 \mathrm{~cm}$

So any measurement will be integral Multiple of LC.

So ans. will be $2.124 \mathrm{~cm}$