A screw gauge gives the following readings when used to measure the diameter of a wire Main scale reading : 0 mm Circular scale reading : 52 divisions Given that 1 mm on main scale corresponds to 100 divisions on the circular scale. The diameter of the wire from the above data is :

0.026 cm 0.26 cm 0.052 cm 0.52 cm

0.052 cm

1oo div = 1 mm 1 div = 0.01 mm ; 52 div = 0.52 mm Total reading = MSR + CSR = 0.52 mm = 0.052 cm