Question

You are given two different vernier callipers A and B having $10$ division on Vernier scale which coincide with 9 division on the main scale each If one units on main scale of A is divided into $10$ parts and that of B into $20$ parts. Find their least count.

Answer 1

VSD=Vernier scale division, MSD=Main scale division.

Given,

(A) : MSD $=\frac{10mm}{10}=1mm$

$10VSD=9MSD$

Then, $1VSD=\frac{9}{10}MSD=0.9MSD$

So, the least count is $1MSD-0.9VSD=0.1mm$

(B) : MSD $=\frac{10mm}{20}=0.5mm$

$10VSD=9MSD$

Then, $1VSD=\frac{9}{10}MSD=0.9MSD$

So, the least count is $1MSD-0.9VSD=0.1MSD=0.05mm$