The least count of the main scale of a ***** gauge is 1mm. The minimum number of divisions on its circular scale required to measure 5mm diameter of a wire is :
(1) 100
(2) 200
(3) 50
(4) 500
The correct option (2) 200
Explanation:
1C.*.d = 5 x 10-6 = (1 x 10-3)/N
N = 1000/5 = 200
