Question

What is the reading of the following screw gauge?

• A. 6.74 mm
• B. 7.14 mm
• C. 7.74 mm
• D. 8.14 mm

Answer 1

The correct option is B

7.14 mm

First part of the measurement, P.S.R = 7 mm

Head scale division that coincides with the pitch scale axis, H.S.C = 14

Second part of the measurement, H.S.C $\times$ L.C = 14 $\times$ 0.01 mm = 0.14 mm

Measurement with zero error = P.S.R + H.S.C $\times$ L.C = 7 + 0.14 = 7.14 mm