Question

the screw advences by 1 division on main scale when circular head is rotated once.
i)pitch of the screw gauge
ii)least count of the screw gauge
iii)the diameter of the wire​

Answer 1

Explanation:

Pitch is the linear distance traveled by one complete rotation of circular scale.

Since, 1 division travel in main scale so the pitch will be 1 mm.

Least count, LC=p/n

Here, pitch p=1mm and total number of circular divisions n=50

So, LC=1/50=0.02 mm

Diameter of the wire, d= main scale reading (MSR ) +[ circular scale reading (CSD) ×LC]=4+[47×0.02]=4.94 mm