Question

A screw gauge having 100 equal divisions
is used to measure the diameter of a wire
of length 5.6 cm. The main scale reading
is 1 mm and 47th circular division
coincides with the main scale. Find the
curved surface area of wire in cmºto
appropriate significant figure.
( use r = 22/7).
(A) 2.6 cm? (B) 1.6 cm?
(C) 2.7 cm
(D) 1.7 cm?
is to be​

Answer 1

Answer:

Answer

Correct option is

A

2.6

L.C. of the screw gauge =

Numberofdivisionsoncircularscale

Pitch

=

100

1

=0.01mm

Given : Main scale reading =1 mm

Circular scale reading =0.01×47=0.47

∴ Diameter of wire = Total reading =1.47mm=0.147cm

Curved surface area = π×dl=π×(0.147)(5.6)=2.586≈2.6cm

2