The main scale of a vernier calliper has n divisions/cm. n divisions of the vernier scale coincide with (n-1) divisions of main scale. The least count of the vernier calliper is,

A $\frac{1}{(n+1)(n-1)}$ cm

B $\frac{1}{n}$ cm

C $\frac{1}{n^2}$ cm

D $\frac{1}{n(n+1)}$ cm

The answer is C.

Solution

$n\ VSD=(n-1)\ MSD \Rightarrow 1\ VSD=\frac{n-1}{n}$ MSD. LC $=1\ MSD-1\ VSD=\frac{1}{n}$ MSD $=\frac{1}{n}\times\frac{1}{n}$ cm $=\frac{1}{n^2}$ cm.

Concept Vernier callipers - least count

53 questions from this chapter have appeared across 25 exam years.