15. In a vernier callipers each main scale division is of
one mm. Now if 10 vernier scale divisions coincide
with 9 main scale divisions then the least count of
the vernier callipers is
Answers
Given :
In a vernier callipers each main scale division is of 1mm.
10 vernier scale divisions coincide with 9 main scale divisions
To Find :
Least count of the vernier callipers.
Solution :
As given that : 10 VSD = 9 MSD
- VSD = Vernier scale division
- MSD = Main scale division
∴ 1 VSD = (9/10) MSD .......... (I)
Least count of vernier callipers is given by
➙ LC = least count = 1 MSD - 1 VSD
From the first equation;
➙ LC = 1 MSD - (9/10) MSD
➙ LC = [(10 - 9) / 10] MSD
➙ LC = 1/10 MSD
We are given that, 1 MSD = 1mm
➙ LC = 1/10 × 1mm
➙ LC = 0.1 mm
Knowledge BoosteR :
- Least count errors are random errors but within a limited size; they occur with both random and systematic errors.
- The accuracy of measurement is related to the systematic errors but its precision is related to the random errors, which include least count error also.
Let,
VSD = Vernier scale division
MSD = Main scale division
- 10 vernier scale divisions coincide with 9 main scale divisions. [10 VSD = 9 MSD]
- Each main scale division is of 1mm.
Least count of the vernier callipers.
Given value: 10 VSD = 9 MSD
∴ 1 VSD = (9/10) MSD be 1st equation
Least count of vernier callipers is given by
➙ LC = least count = 1 MSD - 1 VSD
From the first equation;
➙ LC = 1 MSD - (9/10) MSD
➙ LC = [(10 - 9) / 10] MSD
➙ LC = 1/10 MSD
From given value that, 1 MSD = 1mm
➙ LC = 1/10 × 1mm
➙ LC = 0.1 mm