A screw gauge having `100` equal division and a pitch of length `1mm` is used to measue the diameter of a wire of length `5.6cm`. The main scale reading is `1mm and 47^(th)` circular division coincides with the scale. Find the curved surface area of wire in `cm^(2)` to appropriate significant fihure.
`(use pi = (22)/(7)`

Explanation

Least cont `= (1mm)/(100) = 0.1mm`
Diameter `= MSR + CSR(LC) = 1mm+47 (0.01)mm = 1.47mm`
Surface area `= pi Dt = (22)/(7) xx 1.47xx56mm^(2)`
`= 2.58724cm^(2) = 26cm^(2)`