Question

The distance advanced by screw of a screw gauge is 2 mm in 4 rotations. Its cap has 50 divisions. If the screw reads 3 divisions on the main scale and 32 on the cap, then the radius is –

• A. 1.82 mm
• B. 3.32 mm
• C. 0.91 mm
• D. 1.66 mm

Answer 1

Answer: (C)

0.91 mm

Answer 2

P = 0.5, Least count = 0.01

2r = 3 × 0.5 +

32 × 0.01 = 1.5 + 0.32 = 1.82 mm

r = 0.91 mm