Question

The pitch of a screw gauge is 1 mm and there are 100 divisions on the circular scale. In measuring the diameter of a sphere there are six divisions on the linear scale and forty divisions on circular scale coincides with the reference line. Find the diameter of the sphere.

• A. $34mm$
• B. $46mm$
• C. $6.4mm$
• D. $62mm$

Answer 1

The correct option is C $6.4mm$

Least count of the screw gauge is $L.C=$ pitch / number of circular divisions $=1/100=0.01mm$

Linear scale reading (LSR) $=6\times 1mm=6mm$

Circular scale reading (CSR) $=40$

Diameter of the sphere $=LSR+(CSR\times L.C)=6+(40\times 0.01)=6.4mm$