There are two Vernier calipers both of which have `1cm` divided into `10` equal divisions on the main scale. The vernier scale of the calipers `( c_(1))` has `10` equal divisions that correspond to `9` main scale divisions. The Vernier scale of the other calipers `( C_(2))` has `10` equal divisions tgat correspond to `11` main scale divisions. the reading of the two calipers are shown in the figure. the measured values (in cm) by calipers `C_(1) and C_(2)` respectively, are

Options

A. 2.87 and 2.87
B. 2.87 and 2.83
C. 2.85 and 2.82
D. 2.87 and 2.86

Answer

(b)

Explanation

For vernier `C_1,`
10 VSD = 9 MSD = 9 mm
:. 1 VSD = 0.9 mm
LC= 1 MSD -1 VSD
= (1 - 0.9)mm = 0.1 mm
`Reading of C_1 = MSR + (VSR)xx LC`
= 28 mm + 7(0.1) = 28.7 mm
=2.87 cm
For vernier `C_2` (which of abnormal), we can show that Reading of `C_2= 28.3 mm`
=2.83 cm