Question

The smallest division on the main scale of a vernier calliers is 1 mm, and 10 vernier divisions coincide with 9 main scale divisions. While measuring the diameter of a sphere, the zero mark of the vernier scale lies between 2.0 and 2.1 cm and the fifth vernier scale coincide with a scale division. Then diameter of the sphere is

• A. 2.05 cm
• B. 3.05 cm
• C. 2.50 cm
• D. None of these

Answer 1

Answer: (A)

2.05 cm

$\begin{array}{c}\text{least count of Vernier callipers}=0.1mm\\ \text{Main scale reading}=2cm\text{.}\\ \text{Vernier scale reading}=5\times 0.1mm=0.05cm\\ \text{Diameter of sphere}=2+0.05cm\\ =2.05cm\end{array}$