Question 108: Units , Dimensions and Error Analysis

Question

In an experiment to find out the diameter of wire using screw gauge, the following observations were noted :
(A) Screw moves $$0.5 \mathrm{~mm}$$ on main scale in one complete rotation
(B) Total divisions on circular scale $$=50$$
(C) Main scale reading is $$2.5 \mathrm{~mm}$$
(D) $$45^{	ext {th }}$$ division of circular scale is in the pitch line
(E) Instrument has 0.03 mm negative error
Then the diameter of wire is :

Accepted Answer

L.C. = $${{0.5} \over {50}}$$ mm = 0.01 mm
$$d = (2.5 + 45 	imes 0.01 + 0.03)$$ mm
= 2.98

Answer

2.92 mm

Answer

2.54 mm

Answer

2.98 mm

Answer

3.45 mm

Units , Dimensions and Error Analysis

Choose the correct answer: