Question

A vernier calipers has `1mm `marks on the main scale. It has `20` equal divisions on the Verier scale which match with `16` main scale divisions. For this Vernier calipers, the least count is
A. `0.2 mm`
B. `0.05 mm`
C. `0.1 mm`
D. `0.2 mm`

Answer 1

Correct Answer - D
Least count of vernier callipers
`LC=1MSD= -1VSD`
`=("Smallest division on main scale")/("Number of divisions on vernier scale")`
`20` divisions of vernier scale `=16` divisions of main scale
`:. 1VSD=(16)/(20)mm=0.8mm`
`LC=1MSD-1VSD`
`=1mm-0.8mm`
`=0.2mm`