Question

For the screw gauge shown below, the least count is 0.01 mm. What is the zero correction?

• A. – 0.95 mm
• B. + 0.95 mm
• C. – 0.05 mm
• D. + 0.05 mm

Answer 1

The correct option is B

+ 0.95 mm

As the zero of the head scale lies above the pitch scale axis, the zero error is negative.

Zero Error = – (100 – 5) $\times$ L.C = – 95 $\times$ 0.01 mm = – 0.95 mm

Hence, Zero Correction = + 0.95 mm