Question

A vernier callipers has 1 mm marks on the main scale. It has 20 equal divisions on the Vernier scale which match with 16 main scale divisions. For this Vernier callipers, the least count is

(A) 0.02 m 

(B) 0.05 mm 

(C) 0.1 mm 

(D) 0.2 mm

Answer 1

Answer is (D) 0.2 mm

20 VSD = 16 MSD

1 VSD = 0.8 MSD

Least count = MSD – VSD

= 1 mm – 0.8 mm = 0.2 mm