Question

A vernier caliper has 10 main scale divisions coinciding with 11 vernier scale divisions. 1 main scale division equals 5 mm. The least count of the device is

(1) 1/2 mm

(2) 5/2 mm

(3) 5/11 mm

(4) 0.3 mm

Answer 1

(3) 5/11 mm

10 M = 11 V

⇒ \(1V=\frac {10}{11} \times 5\,mm\)

⇒ LC = |M - V|

\(=\frac {5}{11} mm\)