Which of the below can be measured using a micrometer screw gauge?

I. Diameter of a small ball bearing.
II. Thickness of pieces of paper.
III. Diameter of a measuring cylinder.
IV. Length of a piece of wire.

A. I, II and IV only.
B. I and II only
C. II and III only
D. III and IV only

Correct Answer:

Option B – I and II only

Explanation

Of all the instruments used in measuring length, the micrometer screw gauge has the highest reading accuracy (0.01 mm) and is therefore used in measuring very small length such as diameter of a small ball bearing, and thickness of a piece of paper.