The pitch of a screw gauge is 1 mm and there are 100 division on the circular scale. While measuring the diameter of a wire, the linear scale reads 1mm and 47th division on circular scale coincides with the reference line. The length of the wire is 5.6 cm. Find the curved surface area `(in cm^2)` of the wire in proper significant figures.

Answer

`2.6 cm^(2)`

Explanation

Least count `= (1 mm)/(100) = 0.01 m`
Diameter `D = 1mm +(47)(0.01)mm=1.47 mm = 0.147 cm`
Curved surface area `= 2 pi l = pi Dl`
`= (3.14)(0.147)(5.6)=2.6 cm^(2)`