Question

The smallest division on the main scale of a vernier callipers 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 lies between 20 and 21 mm and the fifth division of the vernier scale coincide with a main scale division. Then diameter of the sphere is

• A. 20.5 mm
• B. 21.5 mm
• C. 21.50 mm
• D. 20.50 mm

Answer 1

The correct option is A

20.5 mm

$Reading=M.S.R+(L.C)\times (V.S.R)$ $=20+\left(0.1\right)\times 5$ $=20.5mm$