General Physics Ques 29
- A vernier calipers has $1 \mathrm{~mm}$ marks on the main scale. It has 20 equal divisions on the vernier scale which match with 16 main scale divisions. For this vernier calipers, the least count is
(2010)
(a) $0.02 \mathrm{~mm}$
(b) $0.05 \mathrm{~mm}$
(c) $0.1 \mathrm{~mm}$
(d) $0.2 \mathrm{~mm}$
Show Answer
Answer:
Correct Answer: 29.( d )
Solution:
- Least count of vernier calipers
$ \begin{aligned} & \quad \text { LC }=1 \mathrm{MSD}-1 \mathrm{VSD} \\ & =\frac{\text { Smallest division on main scale }}{\text { Number of divisions on vernier scale }} \\ & 20 \text { divisions of vernier scale }=16 \text { divisions of main scale } \\ & \therefore 1 \mathrm{VSD}=\frac{16}{20} \mathrm{~mm}=0.8 \mathrm{~mm} \\ & \therefore \quad \text { LC }=1 \mathrm{MSD}-1 \mathrm{VSD}=1 \mathrm{~mm}-0.8 \mathrm{~mm}=0.2 \mathrm{~mm} \\ & \therefore \text { Correct option is (d). } \end{aligned} $
BETA
